Table 5 Potential transmission lines that would be affected by Cotopaxi and Tungurahua ash and their levels of ash contamination according to the official hazard maps (see Fig. 1), as well as the resulting potential flashover scenarios

COTOPAXI VOLCANO

Hazard Zone

Transmission line

Voltage (kV)

Possible ash thickness (mm)

Contamination scenarios

Potential flashover scenarios

Distal

Santo Domingo – Santa Rosa

230

1 – 10

1–6

3, 4, 5 & 6

Santo Domingo – Esmeraldas

230

1 – 10

1–6

3, 4, 5 & 6

Santo Domingo – Quevedo

230

1 – 10

1–6

3, 4, 5 & 6

Quevedo – San Gregorio

230

1 – 10

1–6

3, 4, 5 & 6

Quevedo – Pascuales

230

1 – 10

1–6

3, 4, 5 & 6

Quevedo – Portoviejo

138

1 – 10

1–6

4, 5 & 6

Quevedo – Chone

138

1 – 10

1–6

4, 5 & 6

Santo Domingo – Esmeraldas

138

1 – 10

1–6

4, 5 & 6

Proximal

Totoras – Santa Rosa

230

 > 100

1–6

3, 4, 5 & 6

Vicentina – Mulaló – Pucará

138

 > 100

1–6

4, 5 & 6

TUNGURAHUA VOLCANO

Distal

Totoras – Ambato

138

3 – 5

1–6

5 & 6

Intermediate

Totoras – Baños – Puyo

138

5 – 8

1–6

5 & 6

Proximal

Totoras – Riobamba – Molino

230

 > 8

1–6

3, 4, 5 & 6