Locations
| Name | Sites | Samples |
|---|---|---|
| Washington County | 1 | 4 |
| Washington County | 1 | 2 |
| Washington County | 6 | 46 |
| Washington County | 1 | 1 |
| Washington County | 4 | 6 |
| Washington County | 3 | 5 |
| Washington County | 1 | 19 |
| Washington County | 9 | 47 |
| Washington County | 2 | 6 |
| Washington County | 2 | 14 |
| Washington County | 1 | 2 |
| Washington County | 155 | 533 |
| Washington Parish | 1 | 2 |
| Watauga County | 5 | 23 |
| Waukesha County | 1 | 2 |
| Wayne County | 1 | 3 |
| Wayne County | 1 | 2 |
| Wayne County | 1 | 2 |
| Wayne County | 2 | 5 |
| Weakley County | 1 | 2 |
| Webb County | 12 | 112 |
| Weber County | 23 | 141 |
| Webster Parish | 1 | 5 |
| Westchester County | 5 | 58 |
| Wharton County | 3 | 8 |
| Wheeler County | 6 | 17 |
| Wilcox County | 2 | 2 |
| Wilcox County | 1 | 1 |
| Wilkin County | 1 | 1 |
| Wilkinson County | 2 | 19 |