Sub-locations
| Name | Sites | Samples |
|---|---|---|
| Pettis County | 1 | 1 |
| Pike County | 6 | 24 |
| Platte County | 18 | 66 |
| Pulaski County | 20 | 63 |
| Putnam County | 0 | 0 |
| Ralls County | 4 | 10 |
| Ray County | 2 | 3 |
| Ripley County | 3 | 18 |
| Saline County | 4 | 23 |
| Scotland County | 0 | 0 |
| Shannon County | 6 | 17 |
| St. Charles County | 8 | 48 |
| St. Clair County | 0 | 0 |
| St. Francois County | 3 | 6 |
| St. Louis County | 10 | 39 |
| Stoddard County | 1 | 4 |
| Stone County | 7 | 14 |
| Taney County | 2 | 6 |
| Warren County | 1 | 4 |
| Washington County | 1 | 1 |
| Wayne County | 1 | 2 |
| Webster County | 1 | 2 |