Sub-locations
| Name | Sites | Samples |
|---|---|---|
| Oakland County | 2 | 12 |
| Oceana County | 1 | 1 |
| Ogemaw County | 1 | 1 |
| Ontonagon County | 1 | 2 |
| Oscoda County | 0 | 0 |
| Ottawa County | 3 | 16 |
| Roscommon County | 3 | 24 |
| Saginaw County | 20 | 82 |
| Schoolcraft County | 1 | 2 |
| Shiawassee County | 1 | 1 |
| St. Clair County | 3 | 2 |
| St. Joseph County | 2 | 5 |
| Van Buren County | 2 | 2 |
| Washtenaw County | 5 | 11 |
| Wayne County | 4 | 8 |