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was the subsidence at Kapoho isolated to the 1975 Kalapana earthquake, or has there been ongoing continuous subsidence after that event. A study by Dr. Benjamin Brooks using Synthetic Aperture Radar Interferometry or (InSAR) was used to determine if the Kapoho areas is actively subsiding. This was one of the many critical aspects of this report and drives, to a certain extent, the recommendations in later chapters. Chapter 2 was written to address the goal in the scope of work related to coastal hazard mitigation: Establish mitigative measures to address the hazards from tsunami and storm wave action and additional catastrophic events facing the existing and potential residential development within the study area. In order to establish mitigative measures, it is necessary to ascertain the relative risks of natural hazards for the area. This was a key component of this report. The InSAR study found that the Kapoho area maybe subject to continuous subsidence 3 of ~0.8 to 1.7 cm/yr +/- 0.8 cm/yr (2 standard deviations). Since subsidence can have a significant influence on other coastal hazards, risks were discussed for earthquakes, hurricanes, tsunamis, and other natural hazards. Hazard mitigation measures for the Kapoho area are also discussed, but presented primarily in Chapter 4. Chapter 3 is devoted to the shoreline certification process, and resolving the issues currently faced by the residents and local government in obtaining a certification when there is monthly or yearly inundation of areas. Specifically the chapter addresses the objective in the scope of work to: Determine the shoreline or identify a methodology to determine the shoreline in the study area. These recommendations shall consider the economic, environmental and legal ramifications resulting from the existing and potential expansion of residential development and seawall improvements within the study area. This Chapter incorporates many of observations that were made during numerous field trips to the site. These field trips provided insight into the difficulty and challenges in implementing the shoreline certification process in the Kapoho area. In addition to the field observations, numerous reports are discussed and recommendations are provided for how the shoreline could be determined. Several options are discussed in this Chapter. One is to use more natural and man-made monuments that approximate the “upper reach of the wash of the waves” and exclude gravity flow as a component of the shoreline determination. This may result in more development pressure on the mauka side of Waiopae Road, which 3 Two standard deviations provides a 95% confidence interval that the true subsidence is within the bracketed accuracy estimation. 7