Sub-locations
| Name | Sites | Samples |
|---|---|---|
| Barnes County | 1 | 1 |
| Benson County | 1 | 13 |
| Billings County | 2 | 2 |
| Bottineau County | 1 | 1 |
| Bowman County | 2 | 4 |
| Burleigh County | 4 | 65 |
| Cass County | 2 | 8 |
| Dunn County | 31 | 101 |
| Emmons County | 5 | 20 |
| Golden Valley County | 1 | 0 |
| Grand Forks County | 1 | 4 |
| Kidder County | 0 | 0 |
| LaMoure County | 3 | 4 |
| McKenzie County | 9 | 52 |
| McLean County | 13 | 62 |
| Mercer County | 33 | 104 |
| Morton County | 5 | 68 |
| Mountrail County | 4 | 14 |
| Oliver County | 17 | 66 |
| Ramsey County | 1 | 4 |
| Ransom County | 2 | 3 |
| Richland County | 1 | 11 |
| Sioux County | 7 | 34 |
| Slope County | 2 | 6 |
| Stark County | 2 | 6 |