| MINERAL SPRINGS WATER SYSTEM | DUBACH, LA | 900 | 6 | — |
| MT OLIVE WATERWORKS DISTRICT | GRAMBLING, LA | 900 | 13 | — |
| HAMMOCK WATER SUPPLY | GILBERT, LA | 900 | 411 | — |
| ATLANTA WATER SUPPLY | WINNFIELD, LA | 900 | 324 | — |
| ARBY'S | COVINGTON, LA | 900 | 20 | — |
| VILLAGES OF BOCAGE- MADISONVILLE | MADISONVILLE, LA | 894 | 18 | — |
| VILLAGE OF ESTHERWOOD WATER SYSTEM | ESTHERWOOD, LA | 891 | 45 | — |
| LISBON WATER SYSTEM | LISBON, LA | 891 | 27 | — |
| MAYFIELD ELEMENTARY SCHOOL | COVINGTON, LA | 890 | 7 | — |
| EAST CENTRAL BOSSIER WATER SYSTEM | BENTON, LA | 885 | 169 | — |
| POINTE A LA HACHE WATER SYSTEM | BELLE CHASSE, LA | 882 | 246 | — |
| BISTINEAU WATER SYSTEM | HEFLIN, LA | 882 | 25 | — |
| CAMERON PARISH WW DISTRICT 9 | GRAND CHENIER, LA | 871 | 292 | Detected |
| MADISONVILLE WATER SUPPLY | MADISONVILLE, LA | 871 | 8 | — |
| GRAPHIC PACKAGING INTERNATIONAL INC - A | WEST MONROE, LA | 850 | 11 | — |
| GRAPHIC PACKAGING INTERNATIONAL INC - B | WEST MONROE, LA | 850 | 10 | — |
| WARD IV WATER DISTRICT | OAKDALE, LA | 840 | 6 | — |
| LAKE RAMSEY | COVINGTON, LA | 840 | 125 | — |
| VARNADO WATER WORKS - PINE | ANGIE, LA | 840 | 13 | Clean |
| PLEASANT HILLS-CROSSROADS WATER SYSTEMS | JOYCE, LA | 840 | 916 | — |
| MAGNOLIA-JACKSON SQUARE | DES PERES, LA | 825 | 64 | — |
| MAGNOLIA-MONEY HILLS ESTATES | DES PERES, LA | 825 | 18 | — |
| MAGNOLIA-RIVER PARK | DES PERES, LA | 822 | 0 | — |
| MARATHON PETROLEUM COMPANY LLC | GARYVILLE, LA | 817 | 73 | — |
| VILLAGE OF MORSE WATER SYSTEM | MORSE, LA | 806 | 43 | — |
| CRESTON WATER SYSTEM | CAMPTI, LA | 801 | 63 | — |
| SPRING BAYOU WATER WORKS DISTRICT | MARKSVILLE, LA | 795 | 34 | — |
| FELLOWSHIP WATER SYSTEM | SIMSBORO, LA | 795 | 32 | — |
| TOWN OF TULLOS WATER SYSTEM | TULLOS, LA | 792 | 626 | — |
| MAGNOLIA-WESTERN UTILITIES, INC | DES PERES, LA | 789 | 66 | — |
| EBARB WWKS DIST # 1 - N EBARB/BELMONT | ZWOLLE, LA | 789 | 328 | — |
| WATERPROOF WATER SYSTEM | WATERPROOF, LA | 786 | 521 | — |
| TOWN OF URANIA WATER SYSTEM | URANIA, LA | 784 | 31 | — |
| COTTON PLANT WATER SYSTEM | GRAYSON, LA | 783 | 87 | — |
| BACKWOOD VILLAGE WATER SYSTEM | SALINE, LA | 783 | 377 | — |
| VILLAGE OF MERMENTAU WATER SYSTEM | MERMENTAU, LA | 780 | 66 | — |
| EBENEZER WATER SYSTEM | CHATHAM, LA | 780 | 82 | — |
| MOREHOUSE CENTRAL WS | COLLINSTON, LA | 780 | 79 | — |
| FRIENDSHIP WATER SYSTEM | SALINE, LA | 777 | 307 | — |
| VIXEN WATER SYSTEM | ALEXANDRIA, LA | 774 | 1,090 | — |
| PHILLIPS 66 LAKE CHARLES REFINERY | WESTLAKE, LA | 770 | 53 | — |
| TICKFAW WATER SYSTEM | TICKFAW, LA | 764 | 22 | — |
| HALL SUMMIT WATER SYSTEM | HALL SUMMIT, LA | 756 | 44 | — |
| SALEM WATER SYSTEM | FARMERVILLE, LA | 753 | 707 | — |
| PITKIN WATER SYSTEM | PITKIN, LA | 750 | 43 | — |
| SHELL CHEMICAL COMPANY | GEISMAR, LA | 750 | 63 | — |
| SUNNY TIMES 4 LLC | LACOMBE, LA | 750 | 7 | — |
| LAKESHORE HIGH SCHOOL | COVINGTON, LA | 750 | 4 | — |
| VILLAGE OF TANGIPAHOA WATER SYSTEM | TANGIPAHOA, LA | 748 | 183 | — |
| VILLAGE OF WILSON WATER SYSTEM | WILSON, LA | 744 | 50 | — |