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w. At Kula'imano WWTP on September 19-20, 2021,an in-plant spill of approximately 6,240 gallons of untreated sewage occurred at the headworks due to a plugged grit screw and was contained on-site. x. At Hilo WWTP on April 15, 2020, approximately 3,403 gallons of waste activated sludge was spilled to ground due to a disconnected flexible hose during maintenance activities and was contained on-site. y. At Kula'imano WWTP on December 28-29, 2018, approximately 66,000 gallons of secondary treated sewage discharged through the outfall to coastal waters fronting Pepeekeo town when a pump failure caused the disinfection treatment system to fail. z. At Kula'imano WWTP on November 27-28, 2017,approximately 94,666 gallons of primary treated sewage discharged through the outfall to coastal waters fronting Pepeekeo town when the aeration basin treatment system failed due to a power interruption. 23. Operations and Maintenance Affecting Health and Safety: From a review of the records provided by Respondent and observations made during inspections, inspectors have identified potential health and safety concerns due to failure to properly operate and maintain equipment. At Hilo WWTP, significant corrosion of the floating roof at the sludge digester tank prevents operator access due to unsafe conditions. At Hilo WWTP, lightning rod wiring at the top of the sludge digesters had corroded to the point where there was no connection to ground, in an area where there may be potential presence of methane in the digesters, which may create a hazardous condition. At the non-NPDES Kealakehe WWTP facility the EPA inspectors observed hypodermic needles in the primary lagoon due to inadequate influent screening, which pose a risk to operators. 24. Sewer Collection Systems Spills and Operations and Maintenance: Based on a review of the records provided by Respondent, including spill reports and observations made during inspections, inspectors have determined that Respondent is not operating and maintaining its sewer collections systems to prevent sewage spills. Respondent also has not sufficiently assessed the condition of its sewer systems and does not have a program in place to systematically repair, rehabilitate, or replace its aging force mains prior to failure. Based on age, many force mains appear to be reaching their end of life and failure may result in significant spill volumes. Most force mains do not have back-up redundancy in case of failure. A review of sewage spills from the sewer collection systems since 2016 indicates that large spills have occurred primarily due to debris blockage, overflows at pump stations (especially during large storm events), ruptures in force mains, and corrosion. Inspectors have documented the following significant sewage spills (greater than 1000 gallons)from 2017 to December 1, 2022, from the collection systems: a. On May 16, 2021, approximately 67,800 gallons of sewage spilled from the gravity line along Hawaii Belt Road in Papa'ikou, reaching Kapue Stream and ultimately reaching In re County of Hawai'i, Docket No. CWA-309(a)-24-003 Page 8 of 17