| Sampling sites | North | West |
| S1 Grand Plaza | 24 07.816 | 110 21.480 |
| S2 Aeropuerto | 24 07.264 | 110 23.354 |
| S3 Aripez | 24 07.243 | 110 25.081 |
| S4 Cibnor | 24 08.368 | 110 24.859 |
| S5 Zacatecas | 24 10.152 | 110 25.627 |
| S6 Las Palmas | 24 09.697 | 110 24.338 |
| S7 Yate Hundido | 24 08.851 | 110 23.779 |