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Cesspools in Hawaii

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Cesspools are used throughout Hawaii for the disposal of untreated sanitary waste. Discharge of raw, untreated sewage to a cesspool can contaminate oceans, streams and groundwater by releasing disease-causing pathogens and nitrates. Pathogens found in untreated sewage can impact human health by contaminating drinking water or waters used for swimming. Nitrates can damage land or aquatic ecosystems including coral reefs. Groundwater provides approximately 95% of all domestic water in Hawaii.

Most cesspools in Hawaii serve only single-family residences and are not regulated by EPA. However, large-capacity cesspools (LCCs) are subject to EPA’s Underground Injection Control (UIC) regulations, which required all existing large-capacity cesspools to be closed by April 5, 2005. The regulations do not allow for a waiver or extension of the deadline.

Visit the Large-Capacity Cesspools page to learn more and find out if you own or operate a large-capacity cesspool.

Graphic showing different building types: Multi-Unit Residential, Non-Residential, and Home Business, with diagrams of LCCs beneath each. In each LCC a sewer-pipe empties into top of a pit with waste flowing out through perforated sides and open bottom into surrounding soil, flowing down towards groundwater. Large Capacity Cesspools (LCC) are a hole in the ground used to discharge untreated sewage and can serve different building types. Multi-Unit Residential LCC: Cesspool serving multiple residential units (e.g., apartment building, duplex, home with mother-in-law unit). Non-Residential LCC: Cesspool with the capacity to serve 20 or more people in a given day (e.g., commercial and public service buildings). Home Business LCC: Cesspool serving a combined single-family home & a home-based business activity (e.g., beauty salon, childcare center, pet grooming service).

Region 9 UIC Inventory Form

Large-capacity cesspools are considered Underground Injection Control (UIC) wells, and owners and operators of large-capacity cesspools must submit inventory information to EPA. You can use this online form or download Form 7520-16: Inventory of Injection Wells and mail it to the R9 LCC Coordinator.

If you need assistance submitting inventory information, please do not hesitate to contact the R9 LCC Coordinator.

Properly Abandon and Close a
Large-Capacity Cesspool

All owners and operators must properly abandon and close their large-capacity cesspool(s). If you are an owner or operator of a large-capacity cesspool you should contact the Hawaii State Department of Health (HDOH) Wastewater Branch (see 'State Resources', above) for guidance on replacing the large-capacity cesspool with a State-approved wastewater system.

To document proper closure of a large-capacity cesspool that receives 1,000 gallons per day (gpd) or less, you must submit a completed and signed Backfilling Final Completion Report. If the large-capacity cesspool receives more than 1,000 gpd, then you need to contact HDOH/Safe Drinking Water Branch, Underground Injection Control Program (see 'State Resources', above) for proper closure instructions.

All documentation demonstrating large-capacity cesspool abandonment and closure should also be submitted to EPA Region 9's Large-Capacity Cesspool Coordinator.

Hawaii State Department of Health (HDOH)/Wastewater Branch

There are approximately 88,000 cesspools in Hawaii; most of which are small-capacity cesspools. Property owners and operators must comply with all federal and state requirements for cesspools.

The HDOH/Wastewater Branch oversees and permits all onsite wastewater systems, including cesspools. HDOH regulations require that cesspools of any size be upgraded, converted, or closed by January 1, 2050.

Enforcement and Compliance

EPA's enforcement activities are designed to investigate and bring cases against individuals or facilities found in violation of the Safe Drinking Water Act's UIC regulations. Regulated entities found in violation may face an enforcement action and fines. EPA is authorized to issue administrative orders requiring compliance and assessing an administrative civil penalty of up to $23,331 for each day of each violation, up to a maximum penalty of $291,641, against an owner or operator of a large-capacity cesspool that violates the Safe Drinking Water Act.

EPA Region 9 has entered into Consent Agreements with a number of regulated entities in Hawaii, including public agencies, businesses and residential facilities, to address violations of the large-capacity cesspool requirements. These enforcement actions have imposed penalties and resulted in closure of about 1,138 large-capacity cesspools statewide.

EPA is authorized to issue compliance orders and/or assess penalties to violators of the Safe Drinking Water Act’s large-capacity cesspool regulations. However, to encourage owners and operators to voluntarily discover, promptly disclose, and expeditiously close large-capacity cesspools, EPA is willing to forego enforcement actions and penalties under its Self-Disclosed Violations Policies.

Information on how to self-disclose potential large-capacity cesspool violations is available at: EPA's eDisclosure.