| AOAnchor (an Oldcastle Company)-white Marsh Plant | White Marsh | MD | Nonmetallic Mineral Product Manufacturing327999 | — | ◇ UNVERIFIED |
| BCBeavercreek Concrete Plant | Beaver Creek | MD | Nonmetallic Mineral Product Manufacturing327320 | — | ◇ UNVERIFIED |
| BSBetco Supreme INC | Odenton | MD | Nonmetallic Mineral Product Manufacturing327331 | — | ◇ UNVERIFIED |
| BMBluegrass Materials Marriottsville Quarry | Marriottsville | MD | Nonmetallic Mineral Product Manufacturing327310 | — | ◇ UNVERIFIED |
| BMBluegrass Materials Rockdale Quarry | Clear Spring | MD | Nonmetallic Mineral Product Manufacturing327320 | — | ◇ UNVERIFIED |
| BMBluegrass Materials Texas Quarry | Cockeysville | MD | Nonmetallic Mineral Product Manufacturing327992 | — | ◇ UNVERIFIED |
| CRCentral Ready Mix Cambridge Plant | Cambridge | MD | Nonmetallic Mineral Product Manufacturing327320 | — | ◇ UNVERIFIED |
| CEChaney Enterprises | Upper Marlboro | MD | Nonmetallic Mineral Product Manufacturing327320 | — | ◇ UNVERIFIED |
| CIChaney Industries | Annapolis | MD | Nonmetallic Mineral Product Manufacturing327320 | — | ◇ UNVERIFIED |
| CNClayburn - New Savage Works | Grantsville | MD | Nonmetallic Mineral Product Manufacturing327120 | — | ◇ UNVERIFIED |
| CPConcrete Pipe and Precast, LLC | Jessup | MD | Nonmetallic Mineral Product Manufacturing327332 | — | ◇ UNVERIFIED |
| CCCrouse Construction CO INC | Aberdeen | MD | Nonmetallic Mineral Product Manufacturing327999 | — | ◇ UNVERIFIED |
| DGDaniel G. Schuster Concrete/h | Hagerstown | MD | Nonmetallic Mineral Product Manufacturing327320 | — | ◇ UNVERIFIED |
| ECEquality Concrete - Seat Pleasant | Seat Pleasant | MD | Nonmetallic Mineral Product Manufacturing327320 | — | ◇ UNVERIFIED |
| GEGardner, E.l.,inc. - Pasadena Plant | Pasadena | MD | Nonmetallic Mineral Product Manufacturing327320 | — | ◇ UNVERIFIED |
| JRJessup Ready Mix Concrete | Jessup | MD | Nonmetallic Mineral Product Manufacturing327320 | — | ◇ UNVERIFIED |
| KAKeymar Aggregates Engineering | Keymar | MD | Nonmetallic Mineral Product Manufacturing327320 | — | ◇ UNVERIFIED |
| LALafarge Aggregates & Concrete | Frederick | MD | Nonmetallic Mineral Product Manufacturing327320 | — | ◇ UNVERIFIED |
| LJLafarge Joppa Concrete Batch Plant | Joppa | MD | Nonmetallic Mineral Product Manufacturing327320 | — | ◇ UNVERIFIED |
| LMLaney Materials LLC - Laney Recycling and Aggregates | Laurel | MD | Nonmetallic Mineral Product Manufacturing327992 | — | ◇ UNVERIFIED |
| LILocke Insulators INC | Baltimore | MD | Nonmetallic Mineral Product Manufacturing327110 | — | ◇ UNVERIFIED |
| MEMaier, Ernst, INC. | Bladensburg | MD | Nonmetallic Mineral Product Manufacturing327331 | — | ◇ UNVERIFIED |
| MCMaryland Concrete Septic Tank INC. | Maryland Line | MD | Nonmetallic Mineral Product Manufacturing327332 | — | ◇ UNVERIFIED |
| MPMaryland Paving Churchville | Bel Air | MD | Petroleum and Coal Products Manufacturing324121 | — | ◇ UNVERIFIED |
| MSMt Savage Firebrick | Frostburg | MD | Nonmetallic Mineral Product Manufacturing327124 | — | ◇ UNVERIFIED |
| MSMt Savage Specialty Refractories | Mount Savage | MD | Nonmetallic Mineral Product Manufacturing327120 | — | ◇ UNVERIFIED |
| NNNew Ngc INC (dba National Gypsum Co) | Belcamp | MD | Chemical Manufacturing325520 | — | ◇ UNVERIFIED |
| OAOldcastle Apg Mid-atlantic Crofton, Md | Odenton | MD | Nonmetallic Mineral Product Manufacturing327331 | — | ◇ UNVERIFIED |
| OPOldcastle Precast INC. | Edgewood | MD | Nonmetallic Mineral Product Manufacturing327390 | — | ◇ UNVERIFIED |
| OMOpta Minerals | Baltimore | MD | Nonmetallic Mineral Product Manufacturing327992 | — | ◇ UNVERIFIED |
| PBPrice Brothers Company | Perryman | MD | Nonmetallic Mineral Product Manufacturing327332 | — | ◇ UNVERIFIED |
| RBRedland Brick | Rocky Ridge | MD | Nonmetallic Mineral Product Manufacturing327120 | — | ◇ UNVERIFIED |
| RMRinker Materials Hydro Conduit- Frederick | Frederick | MD | Nonmetallic Mineral Product Manufacturing327320 | — | ◇ UNVERIFIED |
| RFRockville Fuel and Feed | Rockville | MD | Nonmetallic Mineral Product Manufacturing327320 | — | ◇ UNVERIFIED |
| SCSchuster Concrete Ready Mix Llc-guilford Rd | Jessup | MD | Nonmetallic Mineral Product Manufacturing327320 | — | ◇ UNVERIFIED |
| SCSchuster Concrete Ready Mix Llc-hobbs Rd | Denton | MD | Nonmetallic Mineral Product Manufacturing327320 | — | ◇ UNVERIFIED |
| SCSchuster Concrete Ready Mix Llc-southlawn Ln | Rockville | MD | Nonmetallic Mineral Product Manufacturing327320 | — | ◇ UNVERIFIED |
| SDSchuster, Daniel, INC. | Owings Mills | MD | Nonmetallic Mineral Product Manufacturing327320 | — | ◇ UNVERIFIED |
| SCS&g Concrete Company | Odenton | MD | Nonmetallic Mineral Product Manufacturing327320 | — | ◇ UNVERIFIED |
| SCS&g Concrete Edgewood | Edgewood | MD | Nonmetallic Mineral Product Manufacturing327320 | — | ◇ UNVERIFIED |
| WPWaldorf Plant | Waldorf | MD | Nonmetallic Mineral Product Manufacturing327320 | — | ◇ UNVERIFIED |
| WCWaugh Chapel Plant | Gambrills | MD | Nonmetallic Mineral Product Manufacturing327320 | — | ◇ UNVERIFIED |
| WCWicomico County Airport | Salisbury | MD | Nonmetallic Mineral Product Manufacturing327320 | — | ◇ UNVERIFIED |
| WGWienerberger Group (general Shale) | Beltsville | MD | Nonmetallic Mineral Product Manufacturing327120 | — | ◇ UNVERIFIED |
| YBYork Building Products - Cockeysville | Cockeysville | MD | Nonmetallic Mineral Product Manufacturing327331 | — | ◇ UNVERIFIED |
| AIAmerican Insulated Glass LLC - Baltimore | Ijamsville | MD | Nonmetallic Mineral Product Manufacturing327215 | 20-99 | ◐ LIKELY ACTIVE |
| BRBay Ready Mix of Maryland Llc | Baltimore | MD | Nonmetallic Mineral Product Manufacturing327320 | 20-99 | ◐ LIKELY ACTIVE |
| BPBryantown Plant | Waldorf | MD | Nonmetallic Mineral Product Manufacturing327320 | 20-99 | ◐ LIKELY ACTIVE |
| CCrofton | Crofton | MD | Nonmetallic Mineral Product Manufacturing327331 | 20-99 | ◐ LIKELY ACTIVE |
| CSC.R. Semler Inc | Smithsburg, Md | MD | Nonmetallic Mineral Product Manufacturing327390 | 20-99 | ◐ LIKELY ACTIVE |
