| KCKuhlman Corporation - Yard 1 | Toledo | OH | 20–99 | ◐ LIKELY ACTIVE |
| LNLafarge North America INC Andover Ready Mix | Andover | KS | — | ◐ LIKELY ACTIVE |
| LPLake Placid Cbp | Lake Placid | FL | — | ◐ LIKELY ACTIVE |
| LCLakes Concrete Plus | Bemidji | MN | 20–99 | ◐ LIKELY ACTIVE |
| LRLakeside Ready Mix INC. - Plant No 1 | Abingdon | VA | — | ◐ LIKELY ACTIVE |
| LRLakeside Ready Mix INC - Plant No 2 | Marion | VA | — | ◐ LIKELY ACTIVE |
| LRLaurel Refinery | Laurel | MT | 100–499 | ◐ LIKELY ACTIVE |
| LRLawrence Redi Mix | Bridgewater | MA | — | ◐ LIKELY ACTIVE |
| LSLigonier Stone & Lime Concrete | Latrobe | PA | 1–19 | ◐ LIKELY ACTIVE |
| LCLincoln CO Ready Mix INC | Stanford | KY | — | ◐ LIKELY ACTIVE |
| LRLincoln Ready-mix Concrete | Lincoln | MO | — | ◐ LIKELY ACTIVE |
| LOLion Oil Company | El Dorado | AR | 100–499 | ◐ LIKELY ACTIVE |
| LSLithia Springs Plant 210 | Lithia Springs | GA | 20–99 | ◐ LIKELY ACTIVE |
| LOLive Oak Ready Mix, LLC | Ingleside | TX | 20–99 | ◐ LIKELY ACTIVE |
| LWLone Wolf Enterprises-harrisonville | Harrisonville | MO | — | ◐ LIKELY ACTIVE |
| LRLoughman Ready Mix Plant, Maschmeyer Concrete | Davenport | FL | — | ◐ LIKELY ACTIVE |
| LCL.s. Construction Services (was Licausi) | Independence | MO | — | ◐ LIKELY ACTIVE |
| LOLuebbering Oil CO | Hartsburg | MO | — | ◐ LIKELY ACTIVE |
| LCLunday-Thagard Company, d/b/a World Oil Refining, a California Corporation | South Gate | CA | 20–99 | ◐ LIKELY ACTIVE |
| LILycon INC | Janesville | WI | 100–499 | ◐ LIKELY ACTIVE |
| LRLynchburg Ready-mix Concrete CO INC | Lynchburg | VA | — | ◐ LIKELY ACTIVE |
| LRLynchburg Ready Mix Concrete CO INC - Appomattox | Appomattox | VA | — | ◐ LIKELY ACTIVE |
| MCMabank Cbp No 1 | Mabank | TX | — | ◐ LIKELY ACTIVE |
| MCMajor Concrete 2 New Kings Road Facility | Jacksonville | FL | — | ◐ LIKELY ACTIVE |
| MPMarathon Petroleum Company LP | Findlay | OH | — | ◐ LIKELY ACTIVE |
| MCMarion CO Concrete | Lebanon | KY | — | ◐ LIKELY ACTIVE |
| MRMartinez Refining Company LLC (previously Shell Oil Products Us, Martinez Ref.) | Martinez | CA | — | ◐ LIKELY ACTIVE |
| MPMaryland Portable Concrete Elkton | Elkton | MD | 20–99 | ◐ LIKELY ACTIVE |
| MPMaryland Portable Concrete, INC. | Havre De Grace | MD | — | ◐ LIKELY ACTIVE |
| MHMarysville Hydrocarbons | Marysville | MI | — | ◐ LIKELY ACTIVE |
| MCMaschmeyer Concrete/brooks Street Facility | Lakeland | FL | — | ◐ LIKELY ACTIVE |
| MCMaschmeyer Concrete-hickory Tree Rd | Saint Cloud | FL | — | ◐ LIKELY ACTIVE |
| MCMaschmeyer Concrete Rocket Blvd Facility | Orlando | FL | — | ◐ LIKELY ACTIVE |
| MMMaster Made Tanks, Inc. | Paris | AR | 20–99 | ◐ LIKELY ACTIVE |
| MCMechanicsville Concrete Llc-petersburg Plant | Petersburg | VA | — | ◐ LIKELY ACTIVE |
| MIMedford International Holdings | Medford | OR | 1–19 | ◐ LIKELY ACTIVE |
| MCMesquite Concrete Cuero | Cuero | TX | 1–19 | ◐ LIKELY ACTIVE |
| MMMetromont Materials Corporation - Monroe Plant | Monroe | NC | — | ◐ LIKELY ACTIVE |
| MRMetro Ready Mix Concrete INC. | Nashville | TN | — | ◐ LIKELY ACTIVE |
| MRMetro Ready Mix & Supply Castor Ave Fac | Philadelphia | PA | — | ◐ LIKELY ACTIVE |
| MCMeuth Construction Supply | Henderson | KY | — | ◐ LIKELY ACTIVE |
| MCMeuth Construction Supply - Eddyville Plant | Eddyville | KY | — | ◐ LIKELY ACTIVE |
| MCMeuth Construction Supply INC - Morganfield | Morganfield | KY | — | ◐ LIKELY ACTIVE |
| MCMeuth Construction Supply – Owensboro Plant | Owensboro | KY | — | ◐ LIKELY ACTIVE |
| MCMeuth Construction Supply - Sebree Plant | Sebree | KY | — | ◐ LIKELY ACTIVE |
| MMMeyer Material | Mchenry | IL | — | ◐ LIKELY ACTIVE |
Meyer Utility Structures LLC | Fort Pierce | FL | — | ◐ LIKELY ACTIVE |
| MAMid America Ready Mix - Lyons Plant | Lyons | KS | — | ◐ LIKELY ACTIVE |
| MAMid Atlantic Terminals Shutdown | Chesapeake | VA | — | ◐ LIKELY ACTIVE |
| MCMiddlesboro Concrete Plant | Middlesboro | KY | — | ◐ LIKELY ACTIVE |