Locations
| Name | Sites | Samples |
|---|---|---|
| Dallas County | 1 | 1 |
| Dallas County | 3 | 3 |
| Dallas County | 11 | 85 |
| Dare County | 8 | 21 |
| Darlington County | 1 | 2 |
| Dauphin County | 5 | 53 |
| Davie County | 1 | 3 |
| Davis County | 2 | 48 |
| Dawes County | 1 | 3 |
| Dawson County | 1 | 1 |
| Dawson County | 1 | 2 |
| De Baca County | 2 | 3 |
| De Soto Parish | 2 | 5 |
| Decatur County | 3 | 14 |
| Decatur County | 2 | 5 |
| DeKalb County | 1 | 2 |
| DeKalb County | 1 | 2 |
| Delaware County | 1 | 3 |
| Delaware County | 10 | 36 |
| Delta County | 16 | 95 |
| Democratic Republic of the Congo | 2 | 3 |
| Denmark | 284 | 1036 |
| DeSoto County | 2 | 9 |
| Dewey County | 2 | 7 |
| DeWitt County | 2 | 13 |
| Dixie County | 6 | 44 |
| Dodge County | 3 | 4 |
| Dodge County | 1 | 1 |
| Douglas County | 1 | 2 |
| Drew County | 5 | 7 |