2021-08-25 EMC testimony - (08-23) Demoruelle, Sandra - DEM Request to EPA May 2021

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Unfortunately, the AMP requirement was not anticipated when the EPA approved modifications to the remaining Pahala milestones on September 9, 2019. The County could not proceed with the required geotechnical investigations at the wastewater treatment plant (WWTP) site and within the collection system until the SHPD AMP approval was obtained. The geotechnical and archeological monitoring teams mobilized as soon as possible after the AMP approval was received, and the invasive field work consisting of borings, probing for underground voids which were discovered earlier by geophysical methods, and infiltration testing, commenced on January 18, 2021. The total schedule impact from the unforeseen AMP requirement was 9 months. The preliminary data from the recent geotechnical investigations indicates that the site is feasible for the intended use, but a large number of voids (indicating presumed lava tubes) were identified by subsurface probing. Most of the voids that were found are small (less than 2 feet in height), but there were indications of connections between some of the voids, suggesting a network of voids may be present. A large void measuring 6 feet in height was found under the proposed location of one of the lagoons, as suggested by the earlier geophysical reconnaissance. The width of the void could not be determined but may be 10 feet across or more based on results of adjacent probes. This void represents a significant obstacle to construction of the lagoon as originally designed, and our team continues to work to identify the best path forward for the County with respect to the WWTP configuration at the site. Besides being an obstacle to construction, lava tubes could also present a cultural resource obstacle because of their importance to Native Hawaiians and any archaeological findings could halt the project. In addition to the lava tubes, the WWTP site's topography was discovered to be sloped at a much higher degree than what was assumed in the preliminary engineering report. This new information also will significantly affect the cost of construction. Per your suggestion during our quarterly update call on April 16, 2021, the County will submit an updated plan to EPA with the WWTP option selected from the approved preliminary engineering plan. In the meantime, the County of Hawaii respectfully requests a milestone extension to the July 28, 2021 complete design milestone to July 24, 2022 (to account for the unforeseen nine -month delay caused by the AMP requirement) and an additional three-month extension because of the new information received regarding the site's topography and new geotechnical data. We are on schedule to meet the deadline for the collection system plan and have made great strides with the acquisition of the parcel. The latest information on the land acquisition is we ordered an updated appraisal anticipating the geotechnical findings were forthcoming and that the property would still be acceptable. The final appraisal was completed on April 26, 2021. Negotiations with Kamehameha Schools Bishop Estate (KSBE) have resulted in moving forward with a friendly condemnation. The office of Corporation Counsel is drafting the complaint. As we cannot anticipate if there will be any delays in the courts, we are asking for an additional 9 months (from June 28, 2021 to March 28, 2022) but hope to have the land secured before that.