• Internal Information (policies, strategies, targets, business plans, and risks): To identify key issues through the brainstorming of ideas from executives via workshops, prepare strategies and enterprise risks with possible short- and long-term impacts on organization sustainability.
• External Information (national or global trends and interests): To review national or global trends and interests in alignment with the Sustainable Development Goals (SDGs), Global Reporting Initiative (GRI) Standards, Stock Exchange of Thailand (SET) ESG Ratings, and expectations of stakeholders through formal and informal surveys such as meetings, seminars, interviews, or dialogues as well as opinion and satisfaction surveys with each group of stakeholders.

After the material sustainability topics were identified based on the internal and external factors, the ratings and priorities were given based on 2 evaluation criteria by specifying those topics in the Materiality Matrix which was divided into 2 axes.

• Horizontal axis: Potential impacts from material sustainability topics to stakeholders by considering the likelihood of impactful events, including the Company’s control, prevention, monitoring and audit measures
• Vertical axis: The scope of severity and negative impacts of sustainability topics on stakeholders by determining from the number of stakeholders group affected and the impact on economic and corporate governance dimension, environmental dimension, and social dimension

The material topics obtained from the analysis by the Sustainability Development Working Group of the East Water Group were proposed to the high-level executives for consideration and endorsement. Those topics were also endorsed by the Corporate Governance and Sustainability Development Committee to determine the content covering 3 dimensions namely economic and corporate governance, social, and environmental dimensions.