| MPMidwest Perlite Company, Inc. | Appleton | WI | — | ◇ UNVERIFIED |
| MLM-i LLC - Amelia Grinding & Bulk Storage Facility | Amelia | LA | — | ◇ UNVERIFIED |
| MQMillville Quarry | Baltimore | MD | — | ◇ UNVERIFIED |
| MSMi Swaco Greystone Barite Mine | Battle Mountain | NV | — | ◇ UNVERIFIED |
 Mmc Materials INC | Memphis | TN | — | ◇ UNVERIFIED |
| MMultiserv | Birmingham | AL | — | ◇ UNVERIFIED |
| M1Multiserv/plt 18 Steelton | Steelton | PA | — | ◇ UNVERIFIED |
| MKMurray Keystone Processing Inc/keystone Cleaning Plt | Indiana | PA | — | ◇ UNVERIFIED |
| NLNanocor LLC | Aberdeen | MS | — | ◇ UNVERIFIED |
| NSNevada Slag, INC | Mcgill | NV | — | ◇ UNVERIFIED |
| NENew Enterprise Stone & Lime CO Inc/fairfield | Cumberland | PA | — | ◇ UNVERIFIED |
| NPNorcal Perlite, Inc. | Bakersfield | CA | — | ◇ UNVERIFIED |
| NANorth American Recycling and Crushing LLC | Anaheim | CA | — | ◇ UNVERIFIED |
| NANorth American Recycling & Crushing, LLC. | Colton | CA | — | ◇ UNVERIFIED |
| NSNortheast Solite Corporation | Mount Marion | NY | — | ◇ UNVERIFIED |
| NSNorth Star Water Treatment Facility | Grass Valley | CA | — | ◇ UNVERIFIED |
| ONOil-dri North and South Plant | Ochlocknee | GA | — | ◇ UNVERIFIED |
| OTOil Technology INC | East Chicago | IN | — | ◇ UNVERIFIED |
| OVOmya Verpol Plant | Florence | VT | — | ◇ UNVERIFIED |
| OMOpta Minerals Harseeville Plant | Hardeeville | SC | — | ◇ UNVERIFIED |
| OPOswego Public Works Department | Oswego | NY | — | ◇ UNVERIFIED |
| OCOzinga Cement Incorporated Contractor of Cleveland-cliffs Bu | Burns Harbor | IN | — | ◇ UNVERIFIED |
| OSOzinga Slag LLC | East Chicago | IN | — | ◇ UNVERIFIED |
| PCPacific Custom Materials | Stockton | CA | — | ◇ UNVERIFIED |
| PVPalmetto Vermiculite | Woodruff | SC | — | ◇ UNVERIFIED |
| PSPauls Station of Webster | Rochester | NY | — | ◇ UNVERIFIED |
| PTPebble Technology International | Pearl River | LA | — | ◇ UNVERIFIED |
| PRPenn Rock Aggregates | North Versailles | PA | — | ◇ UNVERIFIED |
| PSPennsy Supply Summit Sta/quarry Wayne Twp | Summit Station | PA | — | ◇ UNVERIFIED |
| PPPerlite Processing Plant | Fallon | NV | — | ◇ UNVERIFIED |
| PVPerlite Vermiculite Packaging Industries INC. | North Bloomfield | OH | — | ◇ UNVERIFIED |
| PSPhoenix Services LLC | Roanoke | VA | — | ◇ UNVERIFIED |
| PIPlacerville Industries | Placerville | CA | — | ◇ UNVERIFIED |
| PSPreferred Sands of Minnesota LLC | Woodbury | MN | — | ◇ UNVERIFIED |
| PIPvp Industries INC. | North Bloomfield | OH | — | ◇ UNVERIFIED |
| RERamrock Environmental | Stockton | CA | — | ◇ UNVERIFIED |
| RBRecology Blossom Valley Organics - South | Lamont | CA | — | ◇ UNVERIFIED |
| RARecycled Aggregate Materials Company INC | Sun Valley | CA | — | ◇ UNVERIFIED |
| RIRedco Ii | North Hollywood | CA | — | ◇ UNVERIFIED |
| RRReflective Recycling of Sc LLC | Pacolet | SC | — | ◇ UNVERIFIED |
| RIRm Industrials - Rm Rail Park Recycle Op | Aurora | CO | — | ◇ UNVERIFIED |
| RIRoss Island Hardtack Island Plant | Portland | OR | — | ◇ UNVERIFIED |
| SPSaint-gobain Proppants (lr) | Benton | AR | — | ◇ UNVERIFIED |
| SCSgl Carbon, LLC | Saint Marys | PA | — | ◇ UNVERIFIED |
| SCSilbrico Corp/easton | Forks Township | PA | — | ◇ UNVERIFIED |
| SCSilbrico Corporation | Brunswick | GA | — | ◇ UNVERIFIED |
| SPSilicon Processors, Inc., Parkersburg | Parkersburg | WV | — | ◇ UNVERIFIED |
| SMSkyline Metals Llc/slag Processing Plt | Baden | PA | — | ◇ UNVERIFIED |
| SCSkyway Cement CO LLC | Chicago | IL | — | ◇ UNVERIFIED |
| SPSlag Plant | El Paso | TX | — | ◇ UNVERIFIED |
| SMSmoky Mountain Transfer Corporation | Charleston | TN | — | ◇ UNVERIFIED |
| SISolem Industries | Fairmount | GA | — | ◇ UNVERIFIED |
| SCSolite CORP | Cascade | VA | — | ◇ UNVERIFIED |
| SCSoutheastern Clay CO | Aiken | SC | — | ◇ UNVERIFIED |
| SCSouthern Clay Products | Gonzales | TX | — | ◇ UNVERIFIED |
| SSSouth Shore Slag LLC - Contractor of Uss Gary Works (00121) | Gary | IN | — | ◇ UNVERIFIED |
| SMSpecialty Minerals (at Madison Paper) | Madison | ME | — | ◇ UNVERIFIED |
| SMSpecialty Minerals INC | Zachary | LA | — | ◇ UNVERIFIED |
| SMSpecialty Minerals INC | Ashdown | AR | — | ◇ UNVERIFIED |
| SVSpecialty Vermiculite CORP | Enoree | SC | — | ◇ UNVERIFIED |
| SCSpinks Clay Company - Gleason Plant | Gleason | TN | — | ◇ UNVERIFIED |
| SCStandard Corporation Jones Lane | Lugoff | SC | — | ◇ UNVERIFIED |
| SIStandard Industrial Mineral in | Laws | CA | — | ◇ UNVERIFIED |
| SMStandard Mineral Company Incorporated | Robbins | NC | — | ◇ UNVERIFIED |
| SIStein, INC | Birmingham | AL | — | ◇ UNVERIFIED |
| SIStein, INC. (old Harsco Metals) | Tarrant | AL | — | ◇ UNVERIFIED |
| SLStein LLC (1318003929) | Cleveland | OH | — | ◇ UNVERIFIED |
| SCSt-gobain Ceramics & Plastics | Bryant | AR | — | ◇ UNVERIFIED |
| SPStreetman Plant | Streetman | TX | — | ◇ UNVERIFIED |
| SMSully Miller Contracting CO | Irwindale | CA | — | ◇ UNVERIFIED |
| SDSuper Dry Industries INC | Shuqualak | MS | — | ◇ UNVERIFIED |
| SPSupreme Perlite Company | Portland | OR | — | ◇ UNVERIFIED |
| SMSuzorite Mineral Products | Dell City | TX | — | ◇ UNVERIFIED |
 Syrah Technologies LLC - Active Anode Material Facility | Vidalia | LA | — | ◇ UNVERIFIED |
| TLTervita LLC | Rancho Cucamonga | CA | — | ◇ UNVERIFIED |
| TRThe R. J. Marshall Company | Southfield | MI | — | ◇ UNVERIFIED |
| TCThermal Ceramics INC | Girard | IL | — | ◇ UNVERIFIED |
| TMT Minerals LLC - Perlite Expansion Facility | New Orleans | LA | — | ◇ UNVERIFIED |
| TITms International, LLC | Broadview Heights | OH | — | ◇ UNVERIFIED |
| TITms International, LLC | Calvert | AL | — | ◇ UNVERIFIED |
| TATrans Agg,inc. Dba Gibbco, INC. | Lawrenceburg | IN | — | ◇ UNVERIFIED |
| TMTreasure Mine | Dillon | MT | — | ◇ UNVERIFIED |
| TUTrebol USA LLC | Andrews | SC | — | ◇ UNVERIFIED |
| TCTube City Ims, LLC | Middletown | OH | — | ◇ UNVERIFIED |
| TITungco INC | Hanson | KY | — | ◇ UNVERIFIED |
| TTTwo Thousand Fahrenheit INC | Becker | MN | — | ◇ UNVERIFIED |
| TOTxi Operations | Streetman | TX | — | ◇ UNVERIFIED |
| UCUnimin Corporation | Gleason | TN | — | ◇ UNVERIFIED |
 United States Gypsum Company | Spruce Pine | NC | — | ◇ UNVERIFIED |
 Universal Minerals International INC. | Louisville | KY | — | ◇ UNVERIFIED |
| UUrbix | Mesa | AZ | — | ◇ UNVERIFIED |
| USU.s. Silica Company, | Middleton | TN | — | ◇ UNVERIFIED |
| USUS Silica Kosse Plant | Kosse | TX | — | ◇ UNVERIFIED |
| USUS Steel Corporation | Lorain | OH | — | ◇ UNVERIFIED |
| VMVanderbilt Minerals LLC | Bath | SC | — | ◇ UNVERIFIED |
| VCVulcan Const Hanover Quarry & Carmeuse Lime Kilns | Hanover | PA | — | ◇ UNVERIFIED |
| VCVulcan Const Mat LP Anderson Quarry | Anderson | SC | — | ◇ UNVERIFIED |
| VCVulcan Construction Material Limited Partnership Pacolet Quarry | Pacolet | SC | — | ◇ UNVERIFIED |
| WPWa317939649 - Pyrotek Incorporated | Spokane Valley | WA | — | ◇ UNVERIFIED |
| WMWaverly Minerals, INC. | Meigs | GA | — | ◇ UNVERIFIED |
