**3.1 The logical framework matrix**

Taking as a reference the logical framework matrix for systemic and integral evaluation of environmental impacts proposed in [20], the logical framework matrices are designed and defined for the integral evaluation of volcanic risk in the scenarios of the onset of crisis and eruption, which is shown in **Tables 3** and **4**.

## **3.2 The process diagram**

**Figure 3** schematizes the process diagram proposed for the integral evaluation of volcanic risk, which is consistent with the previously described conceptual framework.

To apply and develop this methodology is essential to have GIS tools [23], whose specific process includes a series of activities such as the collection and structuring


**Table 3.** *Logical framework matrix for the integral risk assessment—start crisis scenario.*


#### **Table 4.**

*Logical framework matrix for comprehensive risk assessment—eruption scenario.*

#### **Figure 3.**

*Methodological diagram for the integral risk assessment.*

of information; the alphanumeric and geospatial analysis with which it is possible to calculate the threat indexes, vulnerability, and risk at the level of each pixel of the study area; and finally the obtaining of products, such as risk maps for each analysis scenario.

What follows in this process diagram (after the dotted line in **Figure 3**) will be the risk assessment for decision-making in accordance with the retention and transfer of financial risk and with the cost-benefit analysis [24] that allows to define clear, precise, and consensual policy guidelines for land-use planning, as well as the corresponding emergency and contingency plans.

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**Figure 4.**

*Toward a New Conceptual and Methodological Approach for the Integral Evaluation…*

In the application of the conceptual and methodological approach previously exposed, the integral risk assessment is carried out in the Cerro Machín volcano, Colombia [16]. With this process, we obtain, for the scenarios of crisis initiation and eruption, the maps of total risk and the maps with the escape routes and zones of possible shelters for the transitory and/or definitive relocation of population and

According to the logical risk assessment framework, for each analysis scenario considered, the total risk maps are obtained by means of the weighted sum of the

According to the map in **Figure 4**, it can be seen in a general way that for the crisis initiation scenario, the highest total risk indexes are located in the areas near the volcanic building and in the valleys and slopes of the Toche and Bermellón rivers. For the eruption scenario, the high-risk indices are located in the areas exposed to the flows and landslides. The medium- to high-risk indexes are located in areas exposed to falls, characterized by the presence of crops and isolated rural housing.

The determination of escape routes and areas of possible temporary shelters and/or the final relocation of the population and population centers involves solving the following questions: When should evacuations take place? Who should be evacuated? Where and to where should they be evacuated? And so on. The answer

*DOI: http://dx.doi.org/10.5772/intechopen.84415*

population centers, as shown below.

**4.1 Total risk maps**

**4. Case study: the Cerro Machín volcano**

total risks on each exposed element, as shown in **Figure 4**.

**4.2 Exit route maps and areas of possible hostels**

*Total risk duplex map—start of crisis and eruption scenarios.*

*Toward a New Conceptual and Methodological Approach for the Integral Evaluation… DOI: http://dx.doi.org/10.5772/intechopen.84415*
