(BIVN) – The planned closure of existing large capacity “gang” cesspools in Naʻalehu – and the construction of new sewer collection systems to take their place – is examined in a new draft environmental assessment.

Notice of the Draft Environmental Assessment for the Naʻalehu Large Capacity Cesspool Closure was published in The Environmental Notice for September 8th. 

The Hawaiʻi County Department of Environmental Management project “will improve the longevity of the sewer systems in these communities as well as assure compliance with the EPA mandated conversion of LCCs,” a document summary states.

From the Purpose and Need section of the draft EA document:

A portion of the Nā‘ālehu community is serviced by a sewer system that was privately built, owned, and operated by the C. Brewer. The C. Brewer built sewer system discharges sewage into three (3) LCCs. Around 2006, C. Brewer requested that the County construct and maintain a new and improved community sewer system. A County Council Resolution approved the C. Brewer request. In anticipation of C. Brewer’s dissolution, C. Brewer proposed, and the County agreed, to enter into a formal agreement to not only construct and maintain a new and improved community sewer system but to assume ownership of the existing system including the LCCs by April 30, 2010.

As part of this agreement, for the majority of Nā‘ālehu properties connected to the LCCs, C. Brewer committed to complete the line (called a lateral) between the residences and the property line at the edge of the public right-of-way adjacent to the new collection system. It was agreed, if the County did not complete its portion of the work by April 30, 2010, the County would assume pending and unfinished obligations to connect the new laterals installed by C. Brewer to the residences and new collection system when complete. Thus, because that date has passed and the County has not completed installation of the new collection system, this project includes connecting these C. Brewer laterals, which may now need to be replaced, or installing private laterals for currently connected properties if authorized by the property owner and approved by County Council.

Full project Location Map (from the Draft Environmental Assessment for the Naʻalehu Large Capacity Cesspool Closure)

In 1998, the U.S. Environmental Protection Agency (USEPA), promulgated regulations, 40 Code of Federal Regulations (CFR) 144.14, that require the elimination of LCCs. In 1999, EPA issued regulations under the Safe Drinking Water Act’s (SDWA) Underground Injection Control (UIC) Program which prohibited the construction of new LCCs as of April 2000 and required the closure of all existing LCCs by April 5, 2005 (40 C.F.R. § 144.88). Under federal regulations, an LCC is a cesspool which serves multiple dwellings, or for non-residential facilities has the capacity to serve 20 or more persons per day. For the purpose of complying with EPA regulations, the existing LCC’s within the Project Area must be upgraded.

In June 2017, EPA and the County entered into an Administrative Order on Consent (AOC) to close the LCCs serving the Pāhala community by April 2022. Options considered by the County to close the LCCs include construction of a new sewer collection system located within public rightof-way (ROW) and replacement of the existing LCCs with a wastewater treatment plant (WWTP) to address the wastewater treatment and disposal needs of the Nāʻālehu community. The recently Amended AOC that was proposed as of February 14, 2024, requires the LCCs to be closed no later than December 31, 2027.

The County and the EPA voluntarily entered into the initial AOC for the purpose of bringing the County into compliance with the requirements of the Safe Drinking Water Act (SDWA), 42 U.S.C. § 300f, et seq.

EPA has determined that the County, as the current owner and/or operator of three (3) LCCs that serve approximately 164 private residences in the community of Nā‘ālehu, violated and continues to violate the SDWA and its Underground Injection Control program requirements for existing LCCs. A “cesspool” is a “drywell,” which in turn is a “well,” as those terms are defined in 40 C.F.R. § 144.3. LCCs include “multiple dwelling, community or regional cesspools, or other devices that receive sanitary wastes, containing human excreta, which have an open bottom and sometimes perforated sides.

Based on the above, the County has outlined that the purpose and need for the Proposed Action is to comply with the requirements and mandates of the SDWA and Amended AOC, and to ultimately close the three LCCs that serve Nā‘ālehu. Thus, the core purpose of this exercise is to evaluate, gather community input, and make an informed decision on selecting an option or alternative that will allow the County to close the LCCs, and provide a new, SDWA compliant solution for handling wastewater generated by the Nā‘ālehu Community. Closure of the LCCs will eliminate the disposal of untreated sewage into the subsurface which will serve County’s mission to protect underground drinking water sources.

Proposed Naʻalehu Wastewater Treatment Plant site plan (from the Draft Environmental Assessment for the Naʻalehu Large Capacity Cesspool Closure)

The Draft Ea examines a number of alternatives: a package plant and new collection system, a package plant connected to the existing collection system, a maintenance contract model Individual Wastewater System (IWS) program, and a County issued voucher program with an operating permit model IWS program. There is also a No Action Alternative.

The consultant for the Draft EA is Wilson Okamoto Corporation. The statutory 30-day public review and comment period is underway, with comments due by October 8, 2024.