The Hamaoka Nuclear Power Plant in Shizuoka Prefecture has come under scrutiny after the Nuclear Regulation Authority (NRA) revealed on the 25th that irregularities were discovered in the seismic review data. There are suspicions that favorable data may have been used to underestimate the potential seismic motion, known as 'standard seismic motion'. However, the NRA has reported that they were unable to trace the documentation regarding how this was established, as no appropriate business plans were found within the company. The regulatory body has conducted inspections at the headquarters in Nagoya in January and February following the emergence of these data tampering allegations, gathering testimonies from employees about the process involving the compilation of standard seismic motion. Despite these efforts, the NRA failed to locate any individual business plans or documentation to clarify the establishment process, indicating a significant oversight in internal processes at Chubu Electric Power, the operator of the plant. Furthermore, the findings suggested that the plant had not subjected the standard seismic motion to any internal verification or validation process that is typically a part of seismic design. Although records regarding instructions given to contractors for selecting earthquake waves and internal reviews by experts were found, specifics regarding directives or indications of any fraudulent actions were notably absent from the documentation. This raises serious concerns about the integrity and safety protocols in place at the Hamaoka Nuclear Power Plant, an issue that not only affects local stakeholders but also has national implications in terms of nuclear safety and regulatory compliance.