The County of Hawaii (Permittee) owns and operates the facility, located at
150 Kekuanaoa Place, Hilo, Hawaii, on the Island of Hawaii. The facility is a secondary wastewater treatment plant designed to treat domestic wastewater at an average flow of five (5) million gallons per day (MGD) and a peak wet weather flow of 13 MGD. The plant uses a combination of physical, chemical, and biological treatment processes.

Raw wastewater entering the facility first undergoes preliminary treatment consisting of bar screening and grit removal. Following preliminary treatment, the wastewater enters preaeration tanks and primary clarifiers. The wastewater is then pumped to two biotowers for biological treatment, where organisms attached to media break down the organic components in the wastewater. Following this process, the wastewater flows to the solids contact tank for flocculation prior to entering the secondary clarifiers where quiescent hydraulic conditions allow the bacteria to floc together and settle out of the wastewater. The treated effluent leaving the plant is disinfected with a chlorine solution and flows to the ocean via an outfall discharge pipe. The organic solids removed from the wastewater are subjected to additional dewatering and disposed of at an approved landfill.

Treated effluent from the facility is discharged into the Pacific Ocean, through an outfall diffuser system which runs approximately 4500 feet offshore. The diffuser is 210 feet long and located at an average depth of 52 feet, at coordinates: Latitude 19°44’38"N and Longitude 155°02’58"W.

The receiving water, the Pacific Ocean, is classified by the DOH as a Class A, Wet, Open Coastal Water under HAR Section 11-54-6(b). It is the objective of Class A waters that their use for recreational purposes and aesthetic enjoyment be protected. Any other use shall be permitted as long as it is compatible with the protection and propagation of fish, shellfish, and wildlife, and with recreation in and on these waters.

For more information or if you have special needs due to a disability and require aid in inspecting and/or commenting on the public notice permit and related information, please contact Mr. Reef Migita, Supervisor of the Engineering Section, Clean Water Branch, at the above address or (808) 586-4309 (Voice) as soon as possible before the end of the comment period. For those who use a TTY/TDD, please call through Sprint Relay Hawaii, at 1 711 or 1-877-447-5991. If a request for assistance is made after the end of the comment period, the CWB will try to fulfill the request, but cannot guarantee that the request can be fulfilled prior to a final determination.

All written comments and requests received on time will be considered. If the Director determines that there is significant public interest, a public hearing may be held after at least 30 calendar days of public notice.

If CWB believes, after considering all timely written comments and all oral comments at any public hearing that may be held, that no substantive changes to the conditions of the public notice permit are necessary or warranted, then CWB may recommend to the Director that the NPDES permit be issued.