## 10 Discussion on EW Implementation  
An essential element of the HWE slope failure EWP process is constructing a predictive model by integrating field instruments with numerical and analytical data. Numerous influencing factors affected the trend of the prediction model, which is noteworthy. Precipitation, inadequate surface and subsurface drainage, top slope soil surface erosion due to wet-dry cycles, and a poor soil type (expansive soil) all contribute to HWE slope movements. Collecting and analyzing supplementary data pertaining to moving gradients makes it possible to discern additional patterns, enhance confidence in the patterns delineated in this research, and ultimately aid transportation agencies in formulating sound financial and rehabilitation determinations. In light of those aforementioned significant influencing variables on the development of an HWE slope failure EWP, the action research framework of the protocol is indispensable for making final decisions. Table 4 illustrates the EWP action research framework for HWE slopes. The four main components of this action research framework are observation, planning, decision-making, and action. Each of the framework's subcategories must be satisfied for the established EWS for HWE slope failures to be implemented effectively. The framework stipulates that all high-risk HWE slopes in terms of slope failure should be inspected, inventoried, and classified according to failure causes. Then, key available monitoring methods should be planned along with  
Figure 20: Proposed detailed EWP framework. instrumentation plans. A cost analysis will be conducted based on the conditions and priorities. Finally, an evaluation and implementation of the action plan for the stabilizing techniques will take place. The EWP action research framework comprises several stages. This framework aims to improve the understanding of vulnerable highway slopes, develop effective monitoring and predictive models, make informed decisions, and take action to mitigate risks and enhance the safety of these slopes. The methodology can be adapted and extended regionally. To implement the proposed model in other regions and studies (protocol applicability), all regions in the United States (US) and outside the US with characteristics of expansive clay physical index properties could be included. It should be noted that the proposed EWP can function as a program, provided it is equipped with a state HWE slope rating management system and programmed warning sensors. To adopt this proposed protocol, there is no need to have full site-investigated geotechnical parameters. Although the input parameters play an important role in this proposed methodology, the majority of the input parameters are either available from the NOAA (for regional rainfall and air temperature) [34], United States Department of Agriculture (for soil type, soil physical parameters, and groundwater table), or can cost-effectively be extracted from borehole logs (for soil moisture content (SMC)), state reports (for SWRC to obtain soil matric suction (SMS) from SMC), unmanned aerial vehicle surveying (for soil deformation monitoring), and last, but not least, electrical resistivity imaging (for subsurface soil moisture variation). Moreover, to extend prediction-based trend models to prediction-based future models (forecasting), it is necessary to assess the degree of saturation of the HWE slope based on factual rainfall (as an option among all other available methods) and quantify its impact on the slope FS and SVI. The slope saturation degree can then be associated with changes in rainfall patterns, and the future FS and the future slope vulnerability index can be estimated and predicted. Moreover, the EWP is more qualitative (approach-based) than quantitative due to various impacting factors involved in decision-making, which makes it unique for every site condition.