# Assessing Seismic Vulnerability and Pollution Risks of Wastewater Treatment Plants
## 1 Introduction  
Directives 91/271/EEC [1], 98/15/EC [2], and 2008/98/EC [3] lay the legal foundations for properly managing urban wastewater. Additionally, Directive 2000/60/EC [4] established a framework policy for water treatment in the field of water policy. All European countries must follow these rules for better health and environmental protection. Additional national legislation in Greece includes the Joint Ministerial Decision (JMD) 5673/400/1997, as published in Government Gazette (GG) 192B/14-3-1997 [5], GG92A/7-5-2020 [6], and GG405B/3-4-2002 [7]. The organization of the Special Secretariat for Water(SSW) of the Hellenic Ministry of Environment defines the existence of 256 WWTPs throughout the territory [8]. These are controlled by 126 Municipal Sewage Companies [9]. The Water Supply and Sewerage Company of Athens, called \"EYDAP S.A.\", manages the Attica region's water and wastewater. Three zones of seismic hazards indicate the country's potentially harmful areas, according to the Greek Official Gazette 1154/vol. B/12.8.2003 [10]. These hazard data are valuable and exciting for public officers and decision makers. However, the specificity of the data is lacking for possible small-scale building options in the respective area, especially regarding unique or critical constructions. This deficiency is addressed each time with the focused analysis of operational data for specific WWTP projects [11]. Climate change makes it even more imperative to bridge the vulnerability with today's newer data [12]. Combined with building complexity and urbanization, this factor has a more significant impact than earthquakes. Scientists have reviewed the effects on the organic processes of the WWTPs [13]. The triggering of other post-seismic destructions is a common outcome following severe earthquakes. The World Health Organization (WHO) established principles for the prevention and mitigation of disasters via the framework of \"Sendai 2015-2030\" [14]. Prevention and risk mapping are among the framework's most sought-after goals. However, it is remarkable that any recording of structures' impacts in the aftershock period does not include the geospatial distribution of hazardous elements [15]. Nevertheless, specialized surveys and research programs record these data [16] or even attempt to detect the most geospatial-suitable position for establishing a WWTP [17]. In China, pharmaceuticals and other pollutants from these infrastructures were spatially detected in situ [18]. The need for the contribution of qualitative studies, such as expert judgment, is highlighted for assessing seismic vulnerability, which can potentially cause soil-water pollution. A similar survey of the most appropriate sites spatially for WWTPs was conducted through a questionnaire in Loitokitok Kenya [19]. Although the United Nations Office for Disaster Risk Reduction (UNISDR) provides guidelines for risk assessment [20], there is a lack of research regarding the seismic impacts on WWTPs [21; 22; 23; 24], as highlighted by the European Facilities for Earthquake Hazard and Risk (EFEHR) [25]. While seismic vulnerability and impacts on buildings are more frequently documented [26], these studies do not specifically focus on WWTP infrastructures. The vulnerability of critical infrastructure, such as WWTPs, is significant due to poor design and construction when the projects were built, damage over time, and unforeseen circumstances, such as natural disasters. These structures are complex and must be strengthened against structural, non-structural, and operational issues [27]. The potential effects of earthquakes impact the hydrosphere and, ultimately, human health and the environment. The global literature documents these impacts on infrastructure, drainage systems, soil, water, sea, and society. Researchers studying fragility curves classify methods as specific, empirical, analytical, and hybrid [28].