HomeMy WebLinkAbout23-11-14 Pahala Draft Environmental Information Document (Rev. 111423)PAHALA LARGE
CAPACITY CESSPOOL
CLOSURE
Draft Environmental Information Document
- Subject to Change -
Prepared For:
Prepared By:
County of Hawai’i Department of Environmental Management
Wilson Okamoto Corporation
Pahala, Big Island, Hawai’i
November 2023
1 Pāhala Large Capacity Cesspool Closure
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Table of Contents
1. Introduction ........................................................................................................... 4
1.1 Background ........................................................................................................ 4
1.2 Previous Environmental Documentation ................................................................. 4
1.3 Project Location .................................................................................................. 6
1.4 Purpose and Need ............................................................................................... 6
2.Project Description and Alternatives ..................................................................... 9
2.1 Proposed Action .................................................................................................. 9
2.2 Alternative 1: Package Plant New Collection System................................................ 9
2.3 Alternative 2: Package Plant Existing Collection System ......................................... 23
2.4 Alternative 3 – Individual Wastewater System-Maintenance Contract Model ............ 26
2.5 Alternative 4 – Individual Wastewater System-Operating Permit to Homeowners ..... 26
3.Legal Framework and Regulatory Authorities ..................................................... 36
3.1 National Environmental Policy Act (NEPA) of 1969 (as Amended) ......................... 36
3.2 Archaeological and Historic Preservation Act (54 U.S.C. § 312502) ....................... 37
3.3 Bald and Golden Eagle Protection Act (16 U.S.C. § 668-668c) .............................. 38
3.4 Clean Air Act (42 U.S.C. § 7401 et seq.) .............................................................. 38
3.5 Coastal Barrier Resources Act (16 U.S.C. § 3501) ................................................ 39
3.6 Coastal Zone Management Act (16 U.S.C. § 1451) ............................................... 40
3.7 Endangered Species Act (16 U.S.C. § 1531) ........................................................ 47
3.8 Environmental Justice Executive Order 12898 ..................................................... 48
3.9 Farmland Protection Policy Act (7 U.S.C. § 4201) ................................................. 49
3.10 Fish and Wildlife Coordination Act (16 U.S.C § 661) ............................................. 50
3.11 Floodplain Management (Executive Order 11988, as amended by Executive Orders
12148 and 13690) ....................................................................................................... 50
3.12 Magnuson-Stevens Fishery Conservation and Management Act (16 U.S.C. § 1801) 51
3.13 Marine Mammal Protection Act (16 U.S.C. §§ 1361 et seq.) .................................. 51
3.14 Migratory Bird Treaty Act (16 U.S.C. §§ 703 et seq.) ............................................ 52
3.15 National Historic Preservation Act (54 U.S.C. § 300101) ....................................... 52
3.16 Protection of Wetlands (Executive Order 11990 (1977), as amended by Executive
Order 12608 (1997)) ......................................................................................... 54
3.17 Rivers and Harbors (33 U.S.C. § 403) ................................................................. 54
3.18 Safe Drinking Water Act (42 U.S.C. § 300f) ......................................................... 55
3.19 Wild and Scenic Rivers Act (16 U.S.C. §§ 1271-1287) .......................................... 55
3.20 Clean Water Act (33 U.S.C. § 1251 et seq.) ......................................................... 55
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Table of Contents
4. Existing Environment, Impacts, and Mitigation Measures ..................................... 57
4.1 Climate ................................................................................................................... 57
4.2 Physiography .......................................................................................................... 58
4.2.1 Topography ............................................................................................ 58
4.2.2 Geology .................................................................................................. 59
4.2.3 Soils ....................................................................................................... 61
4.3 Water Resources ..................................................................................................... 61
4.3.1 Surface Waters ........................................................................................ 61
4.3.2 Groundwater ........................................................................................... 64
4.4 Agricultural Lands ................................................................................................... 65
4.5 Natural Hazards ...................................................................................................... 67
4.5.1 Sea Level Rise ......................................................................................... 67
4.5.2 Flood and Tsunami Threat ....................................................................... 68
4.5.3 Hurricane and Wind Hazard ...................................................................... 68
4.5.4 Seismic Hazard ........................................................................................ 69
4.5.5 Volcanic Hazard ....................................................................................... 70
4.5.6 Wildfire Hazards ...................................................................................... 71
4.6 Flora and Fauna ...................................................................................................... 72
4.7 Cultural, Historical, and Archaeological Resources ..................................................... 75
4.8 Air Quality and Odors ............................................................................................. 77
4.9 Noise ...................................................................................................................... 78
4.10 Energy and Natural Resources ................................................................................. 80
4.10.1 Energy Sources ....................................................................................... 80
4.10.2 Land Use and Land Use Plans ................................................................... 80
4.11 Roadways and Traffic .............................................................................................. 82
4.12 Hazardous Materials ................................................................................................ 84
4.13 Socioeconomics & Environmental Justice .................................................................. 85
4.14 Sustainability .......................................................................................................... 89
4.15 Human Health And Safety ........................................................................................ 91
4.16 Unresolved Issues ................................................................................................... 93
5. References ................................................................................................................... 96
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List of Figures
Figure 1 Location Map ......................................................................................... 7
Figure 2 Alternative 1 Site Plan ........................................................................... 10
Figure 3 WWTP Overall Site Plan ......................................................................... 13
Figure 4 WWTP Operations Building Floor Plan..................................................... 14
Figure 5 In-Channel Cylindrical System ................................................................ 15
Figure 6 Aerated Grit Chamber ............................................................................ 16
Figure 7 Granular Activated Carbon Scrubber ....................................................... 17
Figure 8 Calcium Hypochlorite Feed System ......................................................... 18
Figure 9 Subsurface Drip Concept for Pāhala ....................................................... 20
Figure 10 Alternative 2 Site Plan ........................................................................... 24
Figure 11 Alternative 3 and 4 Site Plan .................................................................. 27
Figure 12 Typical Septic Tank System ................................................................... 29
Figure 13 Typical IWS with Absorption Tank .......................................................... 33
Figure 14 Typical IWS with Seepage Pit ................................................................. 34
List of Tables
Table 1.1 IWS Percolation Rate and Required Area ................................................ 32
Table 4.1 Demographic, Economic and Social Characteristics of Pāhala and Hawai'i
County ................................................................................................. 86
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1. Introduction
1.1 Background
The Revised Administrative Order on Consent (AOC) (Docket No. SDWA-UIC-AOC-2017-0002,
effective date August 22, 2022 Large Capacity Closure (LCC) requirements for Pāhala outlines
that an Environmental Information Document (EID) must be prepared by the County of Hawai'i
for US Environmental Protection Agency (EPA) approval within 180 days of the approval of the
Pāhala Preliminary Engineering Report (PER), to meet Federal Environmental Review
Requirements.
The Revised AOC §31.a. requires evaluation of four feasible options:
1. A package plant and new collection system (Alternative 1)
2. A package plant connected to the existing collection system (Alternative 2)
3. A maintenance contract model Individual Wastewater System (IWS) program (Alternative
3)
4. A County issued voucher program with an operating permit model IWS program
(Alternative 4)
In addition, to meet the requirements of the EPA, this EID will include:
5. A No Action alternative.
Unlike the previous AOC, which was initiated on June 22, 207, the Revised AOC no longer requires
the WWTP provide secondary treatment of the sewage. As such, the IWS alternatives provide a
method to close the two LCCs without providing a secondary treatment process. The package
plant discussed below will provide the secondary treatment WWTP.
This document is intended to address State and Federal Environmental Review Requirements of
the Revised AOC, including the feasible options and a No Action alternative under the direction
of the County of Hawaii (County) Department of Environment (DEM). The environmental review
is to be consistent with requirements of the National Environmental Policy Act (NEPA) 42 U.S.C.
§ et seq. and documented in the EID, including the necessary consultation compliance with
Section 7 of the Endangered Species Act and Section 106 of the National Historic Preservation
Act which will be updated for the Selected Alternative.
Supporting additional studies include Archaeological and Cultural documentation as well as
Botanical / Faunal Surveys and regulatory coordination as part of this EID. It is understood, the
County will coordinate with the State of Hawai‘i Department of Health (DOH) to ensure timely
review of studies, documents, and necessary concurrences by the State of Hawaiʽi State Historic
Preservation Division (SHPD) and the US Fish and Wildlife Service.
1.2 Previous Environmental Documentation
In February 2020, the EPA and the DEM issued the Final Environmental Assessment (EA) for the
Pāhala Large Capacity Cesspool Replacement Project which was published in the March 8, 2020
issue of the Environmental Review Program’s The Environmental Notice. The Final EA discussed
the proposed wastewater collection system that would be located within five streets in the
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western portion of the community (Maile, ʻIlima, Huapala, Hīnano, and Hala Streets) and three
streets in the eastern portion of the community (Puahala, Pīkake, and Kamani Streets). The Final
EA also discussed the County’s process for identifying alternative sites for the WWTP and the
selection of the preferred project site for the WWTP and effluent disposal system. A total of 9
alternative sites were identified and assessed before selecting the 14.9-acre project site as
preferred alternative. The development was to consist of a headworks and an odor control unit,
an operations building, four lined aerated lagoons, a subsurface flow constructed wetland to
remove nitrogen and an adjacent disinfection system to remove pathogens and four slow-rate
land treatment basins for disposal of the treated effluent. As set forth in the AOC dated June 22,
2017, the County was to provide an industry standard wastewater collection system and a
secondary treatment and disposal facility.
The February 2020 Final EA found no significant impacts are anticipated from construction and
use of the collection system and wastewater treatment and disposal facility. On February 24,
2020, by letter to the State of Hawaii Office of Environmental Quality Control (Environmental
Review Program) the County DEM issued a Finding of No Significant Impact Notice (Joint
NEPA/HEPA) Pahala Large Capacity Cesspool Replacement Project. The letter stated a Finding of
No Significant Impact (FONSI) is determined for this project. The basis for this determination is
set forth in the Final EA Section 8.1.1, which follows the significance criteria set forth in HAR,
Title 11, Chapter 200, Section 12.
Subsequent to the findings of the Final EA/FONSI, as part of the engineering design work,
additional geophysical/geotechnical investigations identified and confirmed a large subsurface
lava tube extended under the proposed aerated lagoons. Further, the community had not been
receptive to the aerated lagoon technology with large open lagoons and the potential for odors
to affect the community.
Based on these considerations, the DEM has determined not to proceed with implementation of
the wastewater treatment and disposal plant concept as previously proposed and to undertake
analysis of the four (4) options / alternatives as set forth in the Revised AOC and the No Action
alternative be evaluated for implementation in the Pāhala community.
This project may be funded by the State of Hawaiʻi Department of Health (DOH) Clean Water
State Revolving Fund (CWSRF) Program. Under the CWSRF program, the project consists of two
parts: Pāhala Large Capacity Cesspool Conversion and Pāhala Wastewater Collection System. The
CWSRF Program was created by the federal Water Quality Act of 1987 and authorizes low interest
loans for the construction of publicly owned wastewater treatment works. In 1988, the Hawaiʻi
State Legislature passed Act 365, now Chapter 342D of the Hawaiʻi Revised Statues (HRS), to
establish the State Water Pollution Control Revolving Fund to receive the federal capitalization
grant. HRS 342D, Part V (Water Pollution Control Financing), and, more specifically, HRS § 342D-
81 set forth that the State’s policy is to promote water pollution prevention and control, including
the use of recycled water, by financing eligible projects consistent with applicable federal and
state laws. The State Revolving Fund receives annual funding from EPA, which the State of Hawai‘i
DOH is then responsible for allocating among eligible projects.
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1.3 Project Location
The community of Pāhala is located about 52 miles southwest of Hilo, in the Ka‘ū District, Island
of Hawaiʻi. The residential area of Pāhala is located west (mauka) of Māmalahoa Highway (State
Route 11) and about 3.8 miles from the shoreline. Most of the community lies between 980 feet
above mean sea level (msl) on the western end and approximately 800 feet above msl on the
eastern end. Figure 1 shows the Pāhala location map.
Even though Ka‘ū was one of the originally settled areas in the Hawaiian Islands, it remains a
vast remote area. Only a fraction of a percent of the Ka‘ū District has been developed with
residential properties, and the remainder is largely used for agricultural purposes or remains
undeveloped. The Ka‘ū District covers about 922 square miles (approximately 590,000 acres),
with over 80 miles of virtually undeveloped coastline. Nearly two-thirds of its total land area is in
the Conservation District. The Ka‘ū District consists of several communities, including the Pāhala
community, which has a population of approximately 2,210 persons according to the US Census
Bureau American Community Survey, 2021. The distance to the communities of Hilo and Kailua-
Kona means that the Ka‘ū District is relatively isolated from the major infrastructure systems
found in those communities, including wastewater treatment and disposal facilities.
The Project Area includes approximately 200 parcels (in whole or in part) and portions of multiple
County of Hawai’i roadways in Pāhala. The Proposed WWTP Site is located adjacent to the
intersection of Maile Street and Hawai’i Belt Road within a 14.9-acre portion of Tax Map Key
(TMK): (3) 9-6-002-018. The Proposed Collection System Area will include five streets in the
western portion of the community (Maile, 'llima, Huapala, Hinano, and Hala Streets) and three
public streets in the eastern portion of the community (Puahala, Pikake, and Kamani Streets).
The two LCCs slated for closure are located within TMKs (3)9-6-002:024 (por.) and 9-6-016:041
(por.).
1.4 Purpose and Need
A portion of the Pāhala community is serviced by a sewer system that was privately built, owned,
and operated by the C. Brewer Company (C. Brewer). The C. Brewer built sewer system
discharges sewage into two (2) large capacity “gang” cesspools. 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 LCC's by April 30, 2010.
As part of this agreement, for the majority of Pāhala and Nāʻālehu 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.1 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.
Island of Hawaii
Legend
Collection System
Disposal and Treatment Site
Streams
FIGURE 1
PROJECT LOCATION MAP
PAHALA LARGE CAPACITY CESSPOOL CLOSURE PROJECT
1 inch = 2,000 feet.
¯
0 2,000 4,0001,000 Feet
0 500250
Meters Mam alah oa Hig hway
ProjectLocation
Hilo
Pahala
Kailua-Kona
Honokaa
Waiaka Source:
State OP &
ESR I
CollectionSystem
Disposal andTreatment Site
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In 1998, the U.S. Environmental Protection Agency (USEPA), promulgated regulations, 40 Code
of Federal Regulations (CFR) 144.14, that require the elimination of large capacity “gang”
cesspools (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.
In June 2017, EPA and the County entered into an Administrative Order on Consent (AOC) to
close the LCCs serving the Pāhala community by June 2021. Options considered by the County
to close the LCCs include construction of a new sewer collection system located within public
right-of-way (ROW) and replacement of the existing LCCs with a wastewater treatment plant
(WWTP) to address the wastewater treatment and disposal needs of the Pāhala community. The
recently revised AOC that became effective on August 22, 2022 requires the LCCs to be closed
no later than July 21, 2026.
As of August 22, 2022, the County of Hawai'i and the EPA voluntarily entered into a Revised
Administrative Order of Consent (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 two (2) Large
Capacity Cesspools (“LCCs”) that serve approximately 109 private residences in the community
of Pāhala and 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 Actionis
to comply with the requirements and mandates of the SDWA and AOC, and to ultimately close
the two LCCs that serve Pahala. 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 Pāhala 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.
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2. Project Description and Alternatives
2.1 Proposed Action
The Proposed Action is to construct facilities which would allow the County to close the 2 LCCs in
Pāhala and thereby meet the compliance requirements of the Revised AOC and the applicable
portions of the Clean Water Act. The Proposed Action would be achieved by any of the 4
alternatives set forth in the Revised AOC and described below.
2.1.1 Alternative 1: Package Plant New Collection System
Under this alternative, the County of Hawaiʻi would perform the following actions:
1. Acquire, or otherwise obtain the right to develop and use, a portion of the Tax Map Key:
9-6-002:018, a 42.5-acre parcel currently owned by B. P. Bishop Estate Trustees
(commonly known as Kamehameha Schools), then construct a new secondary wastewater
treatment and disposal facility within a 14.9-acre portion of the parcel; (See Figure 2)
2. Construct a wastewater collection system, primarily within the public right-of-way (ROW)
and three segments within easements in the Pāhala community, to collect and convey
sanitary waste from the currently connected and accessible (in accordance with Hawai’i
County Code) properties to the new treatment and disposal facility;
3. Close and abandon two LCCs, according to DOH closure procedures; and
4. Abandon the existing wastewater collection system in place.
These actions will be applicable to Alternative 1 and Alternative 2.
Package Plant
The Revised AOC allows for a Package Plant to be constructed to treat and dispose sewage
currently being disposed in the 2 LCCs. The following sections describe the components and
facilities which would comprise the package plant to treat the sewage and dispose the treated
effluent which would be applicable to Alternative 1 and Alternative 2.
The April 2023, Preliminary Engineering Report (PER) provides the technical information related
to analysis used by the County to select the package plant to be used to treat incoming sewage
flows and a method to be used for disposal of effluent from the wastewater treatment plant
(WWTP). As described in the PER, the WWTP and effluent disposal method would be
accommodated within the 14.9-acre Proposed WWTP Site located near the intersection of Maile
Street and Kamehameha Highway (State Route 11). For more information, see Appendix A.
The PER indicated accurately quantifying flow projections for the Pāhala community is necessary
to design an appropriately sized wastewater treatment and disposal facility. The WWTP design
will need to provide sufficient capacity for the existing parcels within the service area, including
newly accessible parcels reflecting currently developed portions of the Pāhala community. This
will allow the County to close the LCCS. The design will provide sufficient area with the WWTP
site for future expansion.
Existing Large
Capacity Cesspool
(LCC 1)
Proposed Pahala
WWTP Site
Existing Large
Capacity Cesspool
(LCC 2)MEYER RDMEYER RDHAU STHAU STHA
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TPAKALANA STPAKALANA ST
PUMELI STPUMELI ST
HOLEI STHOLEI STKOKIO STKOKIO STKEAHI STKEAHI STOHIA STOHIA STILIAU STILIAU STKAU
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PUAHALA STPUAHALA STPIKAKE STPIKAKE STLEHUA STLEHUA STMAILE STMAILE STHAWAII BELT RDHAWAII BELT RDHALA STHALA STPAAUA STPAAUA STP
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FIGURE 2
PAHALA LARGE CAPACITY CESSPOOL CLOSURE PROJECTPAHALA LARGE CAPACITY CESSPOOL CLOSURE PROJECT
ALTERNATIVE 1 SITE PLANALTERNATIVE 1 SITE PLAN
Ka’u High &
Pahala Elementary
School
Ka’u
Hospital
feet
00 1,0001,000 2,000
N
LEGEND
Lots to WWTP
Newly Accessible Lots to WWTP
Proposed Pahala WWTP Site
Pahala Future County Sewer System
Existing Large Capacity Cesspool (LCC)
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HAR Section 11-62-24(b) requires Counties to use their adopted wastewater flow standards to
develop flow projections for WWTPs. Counties are to use the City and County of Honolulu (CCH)
flow standards if they have not adopted their own standards. The County of Hawai'i has not
adopted its own flow standards, so wastewater flow projections were developed using the current
CCH (2017) wastewater standards. However, flow projections based the current wastewater
standards based on urban Honolulu are likely overly conservative for rural communities like
Pāhala.
The PER indicates the amount of wastewater generated within a residence will not exceed the
amount of potable water used by the occupants. Therefore, potable water use records can be
used to estimate wastewater generation rates within existing communities where no combined
sewers are present. The County of Hawaii Department of Water Supply (DWS) provided potable
water use records from January 2015 through June 2021 for the parcels located within the service
area. Analysis of the potable water use records indicates that a 40,000 gpd monthly wastewater
generation rate would reflect the current needs of the service area. Using a 2.5 peaking factor to
estimate the maximum wastewater flow into the collection system results in a maximum
wastewater flow of 100,000 gpd.
As stated in the PER, groundwater can infiltrate into wastewater collection systems during dry
weather, increasing flows to the WWTP. The 2017 CCH standards specify a dry weather infiltration
and inflow (I/I) allowance of 35 gallons per capita per day (gpcd). The previous CCH standards
(dated 1993) specified a dry weather I/I allowance of 5 gpcd for properties located above the
groundwater table. Through the County’s experience at Honokaa evaluating dry weather I/I for
a rural collection system located in Hawai'i Island’s well-drained geology, at elevations hundreds
of feet above sea level and a significant distance from the shoreline, continued use of the 1993
standard for dry weather I/I is appropriate for Pahala and using the 2017 standard would be
overly-conservative.
The 2017 CCH standards specify a wet weather I/I allowance of 3,000 gallons per acre per day
(gpad). Due to larger parcels within the Pahala service area, wet weather I/I estimates are
modified as permitted by the 2017 CCH standards. The modified flows are based on a 50-foot-
wide corridor of sewer laterals from existing or assumed building foundations on the property.
These assumptions significantly reduce the wet weather I/I estimates for the collection system.
The PER evaluated the effluent flow records at the County Honokaa WWTP to provide an
appropriate analysis of the wet weather peaking factors expected at the Pahala facility. The results
of the Honokaa WWTP effluent flow analysis have determined that a peak day wet weather
peaking factor of 6.5 is recommended for the Pahala WWTP design.
HAR 11-62-23.1(i) requires the initiation of a facility planning process when the actual wastewater
flows reach 75 percent of the design capacity of the WWTP, and implementation of the facility
plan must be initiated when actual wastewater flows reach 90 percent of the design capacity. In
anticipation of future development within the Pāhala community, the PER recommend the WWTP
design be rated to treat an average dry weather flow of 95,000 gpd (approximately twice the
projected average dry weather flow) to avoid the potential of having to initiate a facility plan
shortly after the project is constructed. Note, the biological processes in the mechanical WWTP
will need to be sized to treat the peak day dry weather flow of 108,000 gpd, not the average dry
weather flow.
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Based on the above analysis the County applied to DOH for a variance from HAR Section 11-62-
24(b). On January 26, 2002, the DOH granted the variance, which must be renewed every five
years. The variance contains the following conditions:
1. As a minimum, the Pahala Wastewater Treatment Plant (WWTP) shall be designed using
an average dry weather flow of 95,000 gallons per day.
2. Plans for the proposed Pahala WWTP shall be designed in accordance with applicable
requirements of HAR Chapter 11-62 and be submitted to the Wastewater Branch for
review and approval. In addition, the WWTP shall be approved in writing before it may be
used.
3. There is no automatic renewal. Should the applicant wish to renew this variance
application, the applicant must submit an Application for Variance for renewal, 180 days
prior to expiration date.
The PER provides a description of the package treatment facility to be implemented at Pāhala.
The site plan for Pāhala WWTP would occupy a 14.9-acre area within an existing macadamia
orchard and 1,500-foot long by 25-foot wide utility easement within the 42.5-acre parcel near the
intersection of Maile Street and Mamalahoa Highway, (State Route 11, Hawai'i Belt Road). About
4.0 acres of the 14.9-acre area would require removal of the existing macadamia nut orchard to
accommodate the facilities needed to construct the package plant and related facilities. Thus,
about 10.0+ acres would remain as the macadamia orchard which would be available subsurface
disposal of the treated effluent. A security fence would surround the 14.9-acre site. Figure 3
shows the site plan for the WWTP.
The 4.0-acre package plant includes the headworks, grit drying bed, potable water tank, utility
building which includes a blower room, an emergency generator room, electrical room with a
monitor control center, a maintenance and storage room, and restroom, an above ground fuel
storage tank, and an irrigation control tank. Figure 4 shows the operations building floor plan.
As discussed below, the Pāhala package plant will include preliminary treatment, odor control and
secondary treatment, and disposal of the treated effluent. The preliminary treatment system will
include influent flow measurement, influent sampling, screening and grit removal.
Influent flow measurement is recommended in the PER to allow assessment of flows and loads
to the biological treatment process, and to assess the biological treatment process performance.
A Parshall flume will be provided upstream of the screening system to continuously record influent
flow rates.
An automatic refrigerated composite sampler is recommended to allow influent composite
samples to be collected. Influent composite samples, when combined with influent flow
measurement, can be used to calculate influent mass loading rates to the WWTP to assess the
treatment performance and to optimize aeration rates in the biological treatment process.
Screening is recommended to protect the downstream system operations from large objects,
debris, wipes, and rags that can be present in wastewater. The industry trend is towards finer
screening systems that remove greater amounts of debris from the waste stream; screens with
6-millimeter (mm) (¼-inch) openings are frequently used for activated sludge treatment systems.
3
4
15 Pāhala Large Capacity Cesspool Closure
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Finer screens are used upstream of membrane bioreactors to remove hair that can foul the
membranes.
The PER recommended an in-channel cylindrical screen for this installation. The in-channel
cylindrical screen combines screening, screenings washing, dewatering, compacting, and
bagging/disposal within a single unit as shown in Figure 5. For this installation, the headworks
will include one in-channel cylindrical screen, plus a bypass channel with manually cleaned bar
rack.
The PER stated, r emoval of grit is very important to help prevent wear to downstream equipment,
costly service interruptions and repair. Grit is comprised of particles that are heavier than the
organic biodegradable matter in wastewater. Grit particles can consist of sand, gravel, pebbles,
silt, cinders, ground bone, eggshells, coffee grounds, and other materials. Grit in the wastewater
collection and treatment system causes abrasive wear to mechanical equipment, piping, and
appurtenances. Grit can also form deposits in pipelines, channels, and tanks, which reduces
hydraulic capacity and can damage equipment.
Figure 5: In-Channel Cylindrical Screen
Source: PER, 2023
The PER recommended use of aerated grit chambers which are tanks that function specifically to
remove inorganic solids from the wastewater stream as shown in Figure 6. Aerated grit tanks are
designed to induce sufficient vertical velocity to separate organic and inorganic solids. In theory,
inorganic solids have a higher specific gravity than organic solids, and therefore require higher
vertical velocities to keep them in suspension.
Air diffusers placed near one longitudinal tank wall induce a roll in the contents of the grit tank.
This roll creates maximum velocities near the walls and lower velocities at the surface and bottom
of the tank. The lower transverse horizontal velocities allow inorganic particles to settle out and
be transported to the grit hopper by shear-induced currents.
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Aerated grit chamber design is based on providing sufficient hydraulic detention time during peak
wet weather flow conditions. The PER stated it is necessary to provide at least 10 minutes of
detention time to achieve satisfactory grit removal.
Aerated grit tanks can provide excellent grit removal with minimal headloss, but the chambers
themselves require a larger footprint than induced vortex systems. Proper operation of aerated
grit tanks can be difficult under varying hydraulic loads due to the need to make fine adjustments
to the air diffusers.
The headworks is a notorious location for foul odor at a wastewater treatment plant. This odor is
caused by hydrogen sulfide (H2S), which is formed under anaerobic conditions found in the
wastewater collection system. Due to H2S low solubility in wastewater, when there is an excessive
concentration of H2S or if there is turbulence, H2S gas escapes into the atmosphere. This release
produces a distinct rotten egg smell. In addition to H2S, there are other foul odorous compounds
that can be released from wastewater, such as ammonia, amines, diamines, mercaptans, skatole,
and organic sulfides.
Figure 6: Aerated Grit Chamber
Source: PER, 2023
The PER recommended a granular activated carbon (GAC) scrubber be used at the Pahala WWTP
headworks as shown in Figure 7. A GAC scrubber passes odorous air through a bed of activated
carbon, which absorbs the odorous constituents within the pore spaces of the carbon.
Chemical oxidation or reduction of some compounds can also occur. As pore spaces become
occupied, efficiency degrades, and the carbon must be replaced or regenerated. Carbon is most
effective on higher molecular weight molecules such as the organic sulfur compounds, which
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Figure 7: Granular Activated Carbon Scrubber
Source: PER, 2023
makes it the technology of choice. Package GAC scrubbers are available for small headworks and
vessels can be situated vertically, horizontally or radially to optimize footprints and reduce
structure elevation profiles. The County currently operates GAC scrubbers at other facilities and
purchases the GAC media in bulk, which reduces costs.
Secondary treatment process provides 5-day biochemical oxygen demand (BOD5), total
suspended solids (TSS) and nutrient removal via biological treatment.
The PER provided descriptions of various secondary treatment options including advantages,
disadvantages and applicability to the Pahala WWTP. Further, the treatment options were
screened to identify technologies for further evaluation. Based on the analysis, the PER selected
membrane bioreactor (MBR), activated sludge with anoxic selector, and recirculating gravel filter
for use as the Pāhala WWTP.
A membrane bioreactor (MBR) has the smallest footprint of the various biological treatment
systems available and provides the highest quality effluent. An MBR basically combines an
aeration basin with membrane filtration, eliminating the need for tertiary treatment if a very high-
quality effluent is desired for water reuse purposes.
Membranes provide an absolute barrier to large particles; total suspended solids (TSS)
concentrations of the effluent (also known as “filtrate”) are typically less than 1 mg/L. Effluent
from an MBR process can meet stringent water recycling turbidity requirements without an
additional filtration process.
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The main difference between MBRs and other biological treatment technologies is the method of
separating the bacteria from the clean water. MBRs have thin membranes with many thousands
of micro-perforations. Depending on the manufacturer, these perforations are 0.04 to 0.2 microns
(4 to 20 hundred-thousandths of a millimeter) in diameter, too small for the passage of most
microorganisms or other particles present in the wastewater, but large enough to allow the
passage of water molecules.
The MBR facility has a small footprint and the process would produce a high quality effluent.
However, an MBR facility has a relatively high overall capital cost, operation and maintenance
cost and lifecycle costs. Notwithstanding these considerations, the County will use an MBR
package plant at Pāhala.
The proposed effluent management system (subsurface drip irrigation disposal) does not require
a disinfection process to protect human health and the environment because the treated effluent
is dispersed below the ground surface. However, periodic maintenance chlorination of the
subsurface drip system will be required to reduce biofilm fouling within the drip lines.
Calcium hypochlorite is the solid form of hypochlorite used for disinfection. It can be found as a
powder, granules, pellets, or as tablets in concentrations up to 70 percent. Calcium hypochlorite
will degrade in strength at a rate of 3 to 5 percent per year. Once applied to the wastewater, the
chemistry is similar to that for sodium hypochlorite. Calcium hypochlorite decomposes in an
exothermic reaction if exposed to moisture. Figure 8 shows a typical calcium hypochlorite feed
system.
Figure 8: Calcium Hypochlorite Feed System
Source: PER, 2023
Solid calcium hypochlorite is typically applied directly to wastewater at very small WWTPs due to
its ease of use. Specifically, solid calcium hypochlorite is widely available in concentrated form
as powder, pellets, or tablets – consequently, transportation and storage of solid calcium
hypochlorite disinfectant is optimal for small WWTPs such as at Pāhala. Moreover, the County
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utilizes solid calcium hypochlorite as a disinfectant at other plants, so existing supply chain
logistics may be leveraged.
Disposal of effluent is an important consideration at any WWTP. Although the PER discusses
ocean discharge, use of injection wells, water recycling and slow rate land treatment. The
methods were not deemed feasible due to regulatory issues and high costs, including the need
to remove and dispose all the macadamia trees growing on the 14.9-acre site.
Based on the selected MBR treatment process, use of subsurface drip irrigation of the existing
macadamia orchard for disposal of the treated effluent, as described below, will be used at Pāhala.
The PER indicated the results of the effluent management investigation have determined that a
subsurface drip irrigation system as the recommended method of effluent disposal for the Pahala
WTTP.
This concept would retain the existing site topography along with the macadamia nut tree orchard
and use subsurface drip irrigation technology to apply the effluent. Subsurface drip irrigation
would be used to apply effluent to the existing macadamia nut trees within the effluent disposal
area. The use of subsurface drip irrigation technology to disperse effluent at the site will allow
the County to retain the existing mature macadamia nut trees, and will significantly reduce the
amount of clearing, grubbing, and grading required to construct the facility. In addition, retaining
the existing mature orchard is expected to effectively block views of the facility from both the
Hawaii Belt Road and Maile Street.
Drip irrigation technology has evolved to the point where non-clog emitters are available for
subsurface applications of effluent. Non-clog subsurface emitters decrease the potential for the
irrigation components to be clogged by roots. Drip tubing with integral emitters is buried 6 to 9
inches below ground. Effluent emitters are typically designed to operate at a flow rate of 1 gallon
per hour (gph) and are typically spaced every 2 feet along a drip line. Pressure compensating
drip systems typically operate under pressures ranging from 10 to 45 pounds per square inch
(psi). Figure 9 shows the subsurface drip concept.
The effluent disposal system will be sized to handle the peak day wet weather flow of 312,000
gpd. An irrigation equalization and control tank are proposed to equalize higher peak flows and
to allow discrete dosing of the orchard in irrigation zones; constant application of water would be
detrimental to the health of the trees.
HAR 11-62 requires a fully redundant subsurface disposal system. The design criteria are based
on providing a subsurface drip system that is two times larger than needed in order to satisfy the
HAR 11-62 requirement for redundancy. The drip system will be divided into two separate systems
so that the peak day wet weather flow can be disposed on the site using one system while the
second system is out of service for maintenance.
The subsurface drip lines are to be located between the existing row of trees and spaced to
disperse effluent evenly throughout the orchard. During high flow conditions the irrigation control
system will open multiple irrigation zones to accommodate the disposal needs.
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Figure 9: Subsurface Drip Concept for Pāhala
Source: PER, 2023
Additional drip lines will need to be added when the WWTP capacity is expanded. The minimum
spacing between drip lines is 2 feet, so there will be sufficient space between the initial drip lines
to add additional drip lines as part of future expansion project(s).
The PER conducted water balance and nutrient balance to determine the expected nitrogen use
by the macadamia nut orchard. The analysis showed the orchard of mature macadamia nut trees
is expected to use up to 400 lbs. of nitrogen per acre per year (University of Hawaii Agricultural
Experiment Station, January 1959). The effluent will supply approximately 289 lbs./acre/year of
total nitrogen, assuming an effluent concentration of 10 mg/L. Although the nitrogen uptake of
the orchard is expected to be greater than the total mass of nitrogen applied by the effluent, the
predominant nitrogen species in the effluent is expected to be nitrate, which is soluble and readily
transportable through the soil profile. The trees will only be able to use the nitrate contained
within water that is transpired. The percolate volume is expected to contain approximately 8.5
mg/L of nitrogen as nitrate, because soil denitrification losses of 15 percent can be expected.
Therefore, the land treatment system is expected to remove approximately 21 percent of the
total nitrogen applied to the site from the WWTP effluent.
The PER stated drip irrigation technology has evolved to the point where non-clog emitters are
available for subsurface applications of effluent. Non-clog subsurface emitters decrease the
potential for the irrigation components to be clogged by roots. Tubing with integral emitters is
buried 6 to 9 inches below ground. Effluent emitters are typically designed to operate at a flow
rate of 1 gallon per hour (gph) and are typically spaced every 2 feet along a drip line. Pressure
21 Pāhala Large Capacity Cesspool Closure
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compensating drip systems typically operate under pressures ranging from 10 to 45 pounds per
square inch (psi).
Subsurface drip irrigation technology incurs greater operation and maintenance cost than a
surface irrigation system. The County will need to periodically flush the drip lines to remove
debris. As described below, a significant number of drip lines will be necessary to accommodate
peak flow rates. In addition, periodic chlorination will be required to remove biological growth
from the drip lines. These operations and maintenance tasks will need to be completed on a
regular schedule, because the drip system will be buried and not readily accessible or observable.
During periods of dry soil conditions, the County will need to inspect the orchard for patches of
wet soil that would indicate a localized failure that requires repair. Flow and pressure monitoring
will also be useful tools for validating the status of the subsurface drip system. The land treatment
area would be divided into multiple irrigation zones, allowing a zone to be taken out of service
for maintenance purposes. A fence will be constructed around the site to deter entry by humans
and ungulates.
Collection System
Under Alternative 1, the County would construct a new sewer collection system in the Pāhala
community to replace the existing system of substandard gravity lines that convey sewage to the
two LCCs and connect it to the proposed wastewater treatment and disposal facility. The new
collection system would consist of a total of approximately 11,500 linear feet (LF) (2.2 miles) of
corrosion-resistant polyvinyl chloride (PVC) piping almost entirely within the public ROW of eight
public streets. This includes five streets in the western portion of the community (Maile, ʻIlima,
Huapala, Hīnano, and Hala Streets) and three public streets in the eastern portion of the
community (Puahala, Pīkake, and Kamani Streets). The new collection system would service a
total of 174 lots (109 existing or previously connected lots, plus 65 newly accessible lots as
described later in this subsection). The specific number being dependent on the results of the
topographic survey and the design of the collection system that will convey sewage to the new
wastewater treatment and disposal facility.
Similar to the treatment and disposal facility, the collection system would be designed not to
preclude expansion to meet the requirements of Policy 120 of the Ka‘ū Community Development
Plan.
The County would construct the collection system in two phases to ensure that residential units
can maintain access to the sewer system all times. Phase 1 would construct segments totaling
approximately 1,400 LF of 12-inch line and 700 LF of 8-inch line to divert sewage flows from the
existing LCC collection system to the new treatment and disposal facility and extend laterals to
individual properties making them accessible to this portion of the new collection system.
Specifically, Phase 1 would include the following:
1. A new 1,400-LF, 12-inch diameter line within the Maile Street ROW to intercept flows from
the existing system serving ʻIlima, Huapala, Hīnano, and Hala Streets and convey sewage
to the new wastewater treatment and disposal facility. This new line would be sized to
accommodate the future flows from the entire community.
2. A new 700-LF, 8-inch diameter line partially within the Pīkake Street ROW that would
connect the existing collection system above LCC 2 to the new line on Maile Street
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described above. A 350-LF portion of this line would run through an easement on a
privately owned parcel (TMK 9-6-005:044) to access Maile Street from Huapala Street.
3. Phase 2 would complete the new collection system by constructing segments totaling
approximately 9,400 LF of 8-inch line throughout Pāhala, installing pumps on selected
properties, making individual properties accessible to the new collection system and re-
connecting individual properties currently serviced by the existing collection system to the
new collection system. These main lines would range from a 14-inch line on Pīkake Street
to mostly 8-inch lines on the remaining streets and would run primarily within County
ROWs for ease of access. However, an approximately 1,100-LF segment would follow the
existing system alignment in the industrial area between ʻIlima and Maile Streets. The
property (TMK 9-6-005:036) is owned by Edmund Olsen and leased to M L Macadamia
Orchards. The County would obtain an easement for the work proposed within this area.
Construction of the new collection system would involve temporary impacts within the
public ROWs of eight streets.
The streets within the community are under the jurisdiction of the County, with the
exception of a privately owned portion of Pīkake Street for which the County would obtain
an easement. The streets have been improved with asphaltic concrete (AC) surfaces
approximately 22 to 24 feet wide (plus shoulders), and do not have curbs or gutters. Most
of the streets have two travel lanes and have overhead utility poles are located outside
the travel lanes. Residential lots along the streets have driveways with direct access to
the travel lanes. Most shoulder areas have been improved or consist of grassy swales.
Typical sewer trenches would be about 3 feet wide and at least 6 feet deep to allow the
placement of the lines to meet County standards. The existing pavement would be sawcut,
the trench would be excavated (which could require removal of bedrock), the PVC pipe
installed, and then the trench would be backfilled and compacted. The cut portion of the
AC pavement would then be resurfaced with new AC material. Additional resurfacing may
be required where trenches parallel the streets. The collection system would be installed
with the proper horizontal and vertical clearances from existing water system facilities and
concrete jacketing at waterline crossings, where necessary, as recommended by the
County of Hawai‘i DWS Water System Standards.
4. In April 2007, the County entered into an agreement with C. Brewer to eliminate LCCs
from the existing community sewer systems and connect properties discharging to them
to new County collection, treatment, and disposal system. Once the actual costs are
determined, County Council action is still required to approve the expenditure of funds on
private property for existing connections.
All accessible properties would be required to connect to the new wastewater collection system
in accordance with Hawai'i County Code, HCC, § 21-5. The new collection system would be subject
to HCC 21 (Sewers). Specifically, HCC § 21-5 states the following:
“(a) Owners of all dwellings, buildings, or properties used for human occupancy,
employment, recreation, or other purposes, which are accessible to a sewer are required at
their expense to connect directly with the public sewer within 180 days after date of official
notice.
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(b) If, due to rock, wastewater collection system depth, or other construction problems, a
building cannot be practically served, the owner shall install, operate and maintain a
residential pumping station.
(c) The director may grant a variance/exemption of the foregoing connection requirements
to owners of single-family dwellings existing at the time of installation of the public
wastewater system, if the following is found:
(1) There are special or unusual circumstances applying to the subject real property
which exist that render the ability to connect to a wastewater system an extreme
physical or financial hardship; and
(2) There are no other reasonable alternatives; and
(3) The variance is consistent with the general purpose of the chapter and will not be
materially detrimental to public health, safety, or welfare.”
Accordingly, additional newly accessible lots in Pāhala would be required to connect to the new
wastewater collection system after it becomes operational. These other lots are near the existing
service area and are presently connected to individual wastewater systems or cesspools. The
design of the new collection system would include stub-outs to accommodate the eventual
connection of these newly accessible lots. However, the respective lot owners would be
responsible for the design and completion of these connections and for the proper closure of their
individual wastewater systems.
The State of Hawaiʻi Department of Education (DOE) would connect the Ka‘ū High School and
Pāhala Elementary School and the recently completed Ka‘ū Gymnasium and Shelter to the new
collection system. As stated in Section 4.7.2 of the County of Hawai‘i, Department of Public Works,
Final Environmental Assessment and Finding of No Significant Impact, Ka‘ū Gym and Shelter,
Pāhala, Ka‘ū District, April 2012: “In accordance with Section 21-5, Hawai‘i County Code (HCC),
Ka’ū High and Pāhala Elementary School, including the Ka’ū District Gym and Shelter, will be
required to connect to the County sewer system when access becomes available. The State
Department of Education will be responsible for coordinating and constructing the connection to
the sewer system via a branch main on Hala Street and properly closing their onsite system.”
2.1.2 Alternative 2: Package Plant Existing Collection System
Alternative 2 would construct a new package plant and effluent disposal system, as previously
described, and then connect the existing collection system to the package plant. (The package
plant would be the same as previously described in Alternative 1.)
Existing Collection System
In 2004, C. Brewer Company contracted M&E Pacific to perform a sewer system evaluation for
the town of Pāhala. The scope of the study was to investigate and evaluate the physical condition
of the system, compliance with County sewer standards and identify problems associated with
the existing Pāhala system. The findings were documented in The Ka‘ū Sewer System Evaluation
dated December 2004. Figure 10 shows the existing collection system.
Existing Large
Capacity Cesspool
(LCC 1)
Proposed Pahala
WWTP Site
Existing Large
Capacity Cesspool
(LCC 2)MEYER RDMEYER RDHAU STHAU STHA
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FIGURE 10
PAHALA LARGE CAPACITY CESSPOOL CLOSURE PROJECTPAHALA LARGE CAPACITY CESSPOOL CLOSURE PROJECT
ALTERNATIVE 2 SITE PLANALTERNATIVE 2 SITE PLAN
Ka’u High &
Pahala Elementary
School
Ka’u
Hospital
feet
00 1,0001,000 2,000
N
LEGEND
Lots to WWTP
Proposed Pahala WWTP Site
Existing Sewer Manhole
Existing Sewer Mains
Existing Large Capacity Cesspool (LCC)
25 Pāhala Large Capacity Cesspool Closure
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The 2004 study stated, it was estimated that the existing sewer system was built around the
1940s, or over 80+ years ago. The system consists mainly of cast iron pipes and the manholes
of square concrete boxes. The 2004 study found the residential laterals connect to 4-inch lines
which discharge into 6-inch lines that transmit the sewage to the LCCs. The system has 3 to 5
manholes on Maile Street and Pikake Street and one on the commercial parcel on Pikake Street.
The system does not contain pump stations and does not collect storm water.
The 2004 study indicates the Pāhala community sewer system consists of about 3,058 linear feet
of 6-inch diameter and 10,000 linear feet of 4-inch diameter pipelines. T he house laterals in
Pāhala connect to the 4-inch lines which discharge into the 6-inch lines that transmit t he
untreated sewage to the LCCs. The relatively steep grades of the residential subdivision means
the lines are laid at shallow depths. Further, the results of the investigation determined that the
existing sewer lines and manholes do not conform to the County sewer design standards.
As part of the investigation, a smoke test was conducted of the existing system to determine the
location of any fract ures, open joints, holes and sources of inflow. Smoke testi ng involves t he
blowing of smoke into the sewers normally th rough a manhole or other accessible junction.
The smoke used is a non-toxic substance that will not harm humans. pets. food, plants or
other material goods. It will be visible from manhole covers. roof vents and from t he ground
where sewer line tweaks or defects may exist. The purpose of the smoke is to assist in locati ng
pipe defects and t he entry points of storm and other surface waters into the sewers.
Residents of t he specific area for testi ng were notified via a public notice at least one week
prior to the actual testing.
The results of a smoke test performed during the 2004 sewer system evaluation identified 14
locations of line breaks and/or pipe defects and 7 household units with defective sewer vents.
Also, there is evidence of wastewater spill occurring from a manhole located directly
downstream of the commercial property on Pikake St reet. The manhole contained some
accumulation of debris in the well and evidence of wastewater overflow on the adjacent
ground by the existence of particles of tissue and other solids on the ground surrounding t he
manhole. The owner of the residential lot directly downstream of the commercial property
confirmed t he occasional overflow of wastewater from the subject manhole.
The 2004 report did not discuss any subsequent work related to repairs or other corrections to
the reported findings.
The April 2023 PER, indicated the existing sewer system is over 80 years old, long surpassing its
expected lifespan of the system. Further, if chosen to be reused, the system will require extensive
repair and rehabilitation. The recommended alternative, which received overwhelming support
from Pāhala voters in 2004, consists of constructing a new sewer system in the streets to meet
the County sewer standards and to allow the collection system to be owned and operated by the
County.
Nearly 20 years have passed since the 2004 study was completed. In order to reuse the existing
collection system in the future, an updated condition assessment study is recommended to further
identify system deficiencies. Substantial improvements will likely be necessary due to the age of
the system. Also, reusing the existing collection system would require constructing the Phase 1
collection system project described above to tie into the WWTP and close the LCCs.
26 Pāhala Large Capacity Cesspool Closure
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The April 2023 PER stated, although reusing the existing collection system appears to incur lower
life-cycle costs than the other alternatives, reusing the system is not recommended for
implementation. The advanced age of the existing collection system this option means the County
would incur substantial financial and other risks:
• The piping is at the end of its useful service life, and catastrophic failures are likely to
increase in frequency, creating increased risk to public health and the environment.
• Most of the system is located in backyard easements, making it difficult to access and
maintain.
• The option does not address the AOC requirement to connect additional properties, that
are currently not connected to the collection system, to the WWTP.
• System expansion to accommodate sewer flows in additional areas of the town (in
accordance with the Kau Community Development Plan) would not be feasible.
2.2 Alternative 3 – Individual Wastewater System-Maintenance Contract Model
Hawai'i Revised Statutes, Title 14, Taxation, Chapter 235, Income Tax Law, § 235-16.5 defines a
septic system as an IWS that typically consists of a septic tank, piping, and a drainage field where
there is natural biological decontamination as wastewater discharged into the system is filtered
through soil.
The April 2023 PER, stated the State DOH Wastewater Branch is responsible for regulating IWS
systems. The Revised AOC sets forth that the County Hawai‘i must administer a more active
management strategy than is typically found in Hawai'i IWS. The Revised AOC states either a
Model 2 (Maintenance Contract) or a Model 3 (Operating Permit) must be used IWS systems at
Pahala. Figure 11 shows the site plan for both Alternative 3 and 4.
The April 2023 PER indicates for a Model 2 Alternative, the County is to:
• Fund design and manage project construction of the IWS systems;
• Administer and manage a maintenance program for IWS,
o The maintenance program would entail establishing rules and regulations for
monthly fees/penalties, County monitoring and reporting, and IWS educational
information for homeowners.
• Conduct routine maintenance and operate system, and respond to any related trouble
calls; and
• Prepare and submit related notices and reports.
2.2 Alternative 4 – Individual Wastewater System-Operating Permit to Homeowners
The April 2023 PER indicates for a Model 3 Alternative, the County is to:
Figure 11 – Alternative 3 and 4 Site Plan
Existing Large
Capacity Cesspool
(LCC 1)
Existing Large
Capacity Cesspool
(LCC 2)MEYER RDMEYER RDHAU STHAU STHA
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FIGURE 11
PAHALA LARGE CAPACITY CESSPOOL CLOSURE PROJECTPAHALA LARGE CAPACITY CESSPOOL CLOSURE PROJECT
ALTERNATIVES 3 & 4 SITE PLANALTERNATIVES 3 & 4 SITE PLAN
Ka’u High &
Pahala Elementary
School
Ka’u
Hospital
feet
00 1,0001,000 2,000
N
LEGEND
Lots for IWS
Existing Large Capacity Cesspool (LCC)
28 Pāhala Large Capacity Cesspool Closure
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• Fund design and construction of the IWS systems;
• Administer an operating permit program for the IWS system to the homeowners;
• Issues maintenance notice to the homeowner.
Under Alternative 4, the homeowners would be responsible for maintenance scheduling,
contracting and paying for a service provider to conduct the necessary maintenance and/or
responding to trouble calls, monitoring and record keeping of maintenance.
Under Alternative 4, County is evaluating the possibility of either completing the project as a
conventional Design/ Bid/ Build process, or under a voucher program, which the County would
administer. This voucher program the County will grant homeowners with funds to hire
Professional Engineer to design new IWS and, then hire a Contractor to construct IWS. Under the
voucher program homeowners will be responsible to hire and coordinate with Professional
engineer for placement of IWS and overall design of IWS.
Based on the above, regardless of the maintenance responsibility, the County will fund the design
of the IWS systems for Pāhala. The PER identifies two key considerations to ensure the IWS
functions as intended;(1) s ystem size, including the number of bedrooms or flow rate and (2) site
considerations including soil type, slope, drainage patterns and accessibility to the IWS site.
The PER indicated the median residential parcel in Pāhala is about 10,500 square feet (0.24
acres), with some as small as 5,200 square feet (0.12 acres). HAR 11-62-3.1 (2)(A) states 10,000
square feet (0.23 acres) of usable land must be available for each IWS. Of the 174 properties to
be served in this project, 81 have less than 10,000 square feet of total area. Space available for
IWS installation on these properties may be further limited by the presence of existing structures.
Further, the actual placement of the IWS system is limited by setback requirements from property
lines of 5 to 9 feet and structure walls of 5 feet. From a system design perspective, the PER
recommended that systems should also be a minimum of 20 feet from any cut -face slopes present
on a site to avoid surfacing of treated effluent. This is a particularly a constriction to heavily
sloped sites.
The PER noted the Pāhala has a roughly 10 percent grade, although the slopes will vary from
parcel to parcel. HAR 11-62-34 states absorption beds shall not be installed on lands with a slope
gradient of greater than 8 percent. Absorption trenches are permitted on slopes of up to 12
percent. Generally, the various setback and slope requirements mean that the IWS system will
need to be specifically designed for each parcel.
The PER noted it is generally not good practice to install an IWS under an area with traffic loads
or covered with a concrete covered. The presence of traffic loads or concrete pavement will
compress the soil in distribution/effluent disposal system and affects the accessibility of the
system for maintenance. However, it is sometimes unavoidable particularly on parcels with limited
space. In these instances, a system may be installed underneath a driveway or patio provided
the system is designed with traffic rated treatment components. These may include products such
as concrete septic tanks and/or H-20 traffic related chambered disposal beds.
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S eptic Tanks
The PER stated septic tanks are the most common conversion treatment technology installed in
Hawai‘i. A septic tank is an underground chamber made of concrete, fiberglass reinforced
polyester, or plastic, and used for treating and disposing of household wastewater. The tank
contains a mixture of untreated sewage and anaerobic bacteria, which break down the waste and
separate it into three layers: a top layer of scum, a middle layer of liquid effluent, and a bottom
layer of sludge. Septic tanks operate without the need for electrical power. Contractors are
familiar with the process of installing IWS systems.
The septic tank can have two chambers with sewage flows from the home flowing into the first
chamber where the heavy solids will settle to the bottom as sludge and the remaining liquid and
lighter solids floating to the top as scum. The floating liquid will flow to the second chamber
through an opening in the wall where any remaining solids will settle to the bottom and then
effluent will flow to disposal system. Access to the tank will be sealed to retain the anerobic
conditions which will help to control odor.
The liquid effluent flows out of the tank and into a means of disposal, where it is further treated
and dispersed into the soil. According to the PER, the sludge and scum remain in the tank and
must be periodically pumped out by a professional septic service approximately once every three
to five years, depending on usage. Figure 12 shows a typical septic tank.
Figure 12: Typical Septic Tank System
Source: PER, 2023
The April 2023 PER stated there are several types of septic tanks from suppliers in Hawai‘i. The
tanks can be made from concrete, plastic, and reinforced fiberglass polyester which come at of a
variety of price points, each with a set of advantages and disadvantages and materials. Where a
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septic tank is located beneath a vehicular traffic area, a traffic rated concrete septic tank can be
used or a structural concrete slab designed for H-20 loading spanning a non-traffic tank may be
used.
Concrete tanks are durable and less susceptible to collapse. However, concrete tanks can be more
expensive than plastic or reinforced fiberglass tanks and typically require a crane for installation
and can corrode from the effects of acidic sewer gases.
Plastic or polyethylene tanks are less expensive than concrete; resistant to corrosion and may not
require a crane for installation. However, plastic tanks may deform and, if not properly installed,
can float if flooded.
Fiberglass reinforced polyester (FRP) tanks are less expensive than precast concrete tanks,
primarily due to lower shipping and installation costs, typically resistant to corrosion, more rigid
than plastic tanks, and may not require use of a crane for installation.
The April PER indicated the choice of septic tank material will depend on availability, budget, and
site constraints. At a minimum, septic tanks in Hawai‘i must comply with International Association
of Plumbing and Mechanical Officials (IAPMO) material and property standards for septic tanks.
Further, sizing and installation criteria are regulated by HAR 11-62-33. The minimum septic tank
capacity is 1,000 gallons for a household of 4 bedrooms or less and 1,250 gallons minimum for
households of 5 bedrooms. Septic tanks serving households greater than 5 bedrooms will require
a variance from the DOH.
The PER discusses two commonly used IWS effluent disposal methods found in Hawai'i,
absorption bed and absorption trench. Absorption beds are the most common form of IWS
disposal method installed in Hawai‘i today. The absorption bed will require excavation of 6 to 7
feet below grade to accommodate the network of perforated pipes, each a maximum of 100 feet
long and laid in trenches 1.5-3 feet below the finished grade 4-6 feet apart. Each line is laid level
to allow the gravity dispersal of the treated effluent through the length of the pipe before it filters
out and percolates down into the soil. A minimum of 6 inches of gravel is provided below each
pipe. If the percolation rate is faster than one minute per inch, a 3-foot soil replacement layer is
installed under the entire absorption bed. The s oil replacement is to be washed #4 sand or cinder-
soil mix with a percolation rate not faster than one minute per inch. The excavated material from
the absorption bed will need to be removed off the site.
These systems are easy to maintain when connected to an effective treatment system and will
rely on microorganisms in the soil for an added degree of treatment to the effluent as it filters
through the upper oxic layers of the soil matrix. However, absorption beds have a significant
space requirement with current Hawaiian regulations requiring a minimum of 350 square feet for
a 4-bedroom home. This space requirement increases with decreasing hydraulic conductivity of
the soil. Additionally, absorption beds can only be installed on a grade of less than 8 percent.
An absorption trench is a type of subsurface wastewater disposal system that utilizes a trench
filled with gravel or other porous material to filter and distribute wastewater effluent into the
ground. Wastewater is distributed into the trench through a network of pipes, typically made of
PVC or other durable materials. The gravel in the trench acts as a natural filter, allowing the water
to slowly seep into the surrounding soil while also removing impurities with adsorbed beneficial
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bacteria. The trench may be lined with a layer of filter fabric to prevent the gravel from becoming
clogged with soil or other debris. Figure 13 shows typical IWS site plan with absorption bed.
The PER indicated, although not as common as an absorption bed or trench, use of a seepage
pit should be considered for use in Pāhala. Seepage pits are a vertical means of achieving the
percolation area requirements for a disposal system. These systems typically consist of a 15-30-
foot-deep pit lined with stacked precast perforated concrete rings or CMUs, to an internal diameter
of 6 -8 ft. Seepage pits are both less land area intensive and less expensive than absorption beds.
Figure 14 shows typical IWS site plan with seepage pit.
A seepage pit must include a cover which extends at least 12 inches beyond the seepage pit
excavation or over a provided concrete lining. An access hatch must be provided in the concrete
cover to allow inspection and maintenance of the pit. The seepage pit may be designed to be
traffic rated by providing the sufficient strength required in the design of the concrete lining and
cover.
The effective area of the seepage pit is equal to the vertical wall area corresponding to the
effective depth of the pit. Slow percolation rates translate to a larger required absorption area or
deeper pit.
While seepage pits are an approved means of disposal in Hawai‘i, they are often only permitted
when it can be demonstrated that an alternative means of disposal was not possible , i.e.
insufficient land area, steep terrain (greater than 12 percent) or very slow percolation rates (less
than 60 min/inch). Where slow percolation rates present, seepage pits will need to be dug through
the basalt rock layer to reach more porous soils or a variance will be required from HAR 11-62-
34 d(1)b:
Seepage pits shall not be constructed in soils having a percolation rate slower than ten minutes
per inch (weighted average) or where rapid percolation through such soils may result in
contamination of water-bearing formations or surface water.
The PER provides information related to land area needed for IWS systems, which is affected by
the percolation rate of the soil. The information shows the slower the percolation rate, the larger
the land area needed for the IWS system, or in the case of a seepage pit, the deeper the pit
required. The total area for a septic tank and absorption field ranges from about 480 to 765
square feet. In comparison, the land area for septic tank and seepage pit would be about 120
square feet. The Table 1.1 below from the PER shows the percolation rate and the affected area
required for an IWS system.
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Table 1.1: IWS Percolation Rate and Required Area
A-41
J
FIGURE 13
A-42
J
FIGURE 14
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The PER discussed the installation of an IWS can be a relatively invasive process requiring large
equipment like excavators and cranes. Accommodating this equipment often requires the removal
of fencing, destruction of existing trees, landscaping and, in some cases, small structures. Building
footprints as well as overhanging soffits need to be considered in the design and placement of
the IWS. Also, the access path to the IWS needs to be considered when selecting appropriate
IWS system design as well as for future maintenance activities.
Opportunities/methods to resolve access issue include:
• Placement of the IWS system in the front-yard is recommended for parcels without
sufficient paths to accommodate equipment access into the backyard.
• The use of a large crane can be avoided by specifying cast-in-place concrete traffic slab
with a plastic tank instead of a precast traffic-rated concrete tank, especially for
inaccessible locations and vehicle traffic is anticipated.
• Also, it might be possible to access a backyard from a neighbors’ property by temporarily
removing an adjoining fence.
The P ER identified a number of cost implications from an IWS system that a homeowner will face:
• Homeowners currently connected to the LCCs are paying a reduced sewer fee of about
50 percent of the standard sewer rate (Hawai‘i County, 2023). An IWS will either introduce
a full-rate monthly sewer fee or a bill for private maintenance provider to maintain their
new system. It is quite likely that some homeowners don’t see a need to upgrade from
the current system. However, initial opposition to the project has largely been addressed
through the County’s engagement efforts.
• Most homeowners are protective of their private property. Homeowner permission is not
trivial for a project that poses a risk to their landscaping, fences and buildings. Homeowner
satisfaction with the project will be closely linked with the speed and care with which their
properties are upgraded and restored to pre-construction conditions or better.
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3. Legal Framework and Regulatory Authorities
As described above, the County may use CWSFR for construction of the Pahala Large Capacity
Closure project. Since the State Revolving Fund receives annual funding from EPA, the National
Environmental Policy Act (NEPA) of 1969, as amended (42 U.S.C. §§ 4321 – 4347), requires a
federal agency proposing to undertake a project to consider the potential environmental impacts
of the proposed project. Use of federal funds for a project is among the criteria set forth in NEPA
that require preparation of environmental review documentation under NEPA and procedural
requirements at 40 CFR Parts 1500-1508 (Council on Environmental Quality (CEQ) regulations),
and 40 CFR Part 6 (U.S. Environmental Protection Agency (EPA) regulations. This Environmental
Information Document (EID) has been prepared under these guidelines.
The following regulatory requirements apply to this EID and to federal cross cutting regulations
necessary for compliance with the CWSRF program.
3.1 National Environmental Policy Act (NEPA) of 1969 (as Amended)
NEPA was passed in 1969 “to assure that all branches of government give proper consideration
to the environment prior to undertaking any major federal action that significantly affects the
environment.” NEPA requires all federal agencies to prepare Environmental Information
Documents (EIDs), Environmental Assessments (EA) and/or Environmental Impact Statements
(EISs) to assess environmental impacts from project alternatives.
The purpose of NEPA is “to declare a national policy which will encourage productive and
enjoyable harmony between man and his environment; to promote efforts which will prevent or
eliminate damage to the environment and biosphere and stimulate the health and welfare of man,
to enrich the understanding of the ecological systems and natural resources important to the
Nation; and to establish a Council on Environmental Quality,” Sec. 2 [42 USC § 4321].
According to NEPA, it is the continuing responsibility of the federal government to use all
practicable means, consistent with other essential considerations of national policy, to improve
and coordinate federal plans, functions, programs, and resources. NEPA, as amended in 1970,
requires federal agencies to: (a) utilize a systematic, interdisciplinary approach which will ensure
the integrated use of the natural and social sciences and the environmental design arts in planning
and in decision making which may have an impact on man’s environment; (b) identify and develop
methods and procedures, in consultation with the Council on Environmental Quality established
by Title II of this Act, which will ensure that presently un-quantifies environmental amenities and
values may be given appropriate consideration in decision-making along with economic and
technical considerations; and (c) include in every recommendation a detailed statement on the
environmental impact of the Proposed Action; any adverse environmental effects which cannot
be avoided should the proposal be implemented; alternatives to the Proposed Action; the
relationship between local short-term uses of man’s environment and the maintenance and
enhancement of long-term productivity, and; any irreversible and irretrievable commitments of
resources which would be involved in the Proposed Action should it be implemented, Sec. 102
[42 USC § 4332].
This project may be funded by federal funds provided by U.S. Environmental Protection Agency
(EPA) through the State of Hawai‘i's Clean Water State Revolving Fund (CWSRF) Program. As
such, the State of Hawai‘i Department of Health (DOH) must conduct an environmental review of
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projects funded under the CWSRF as required under the Code of Federal Regulations (CFR), using
the EPA-approved State Environmental Review Process. In addition, the State must comply with
the federal cross-cutting authorities set forth in 40 CFR § 35.3145 for the CWSRF.
The CWSRF requirements are set forth as “cross cutters” described as follows.
In addition to the cross cutters required by the EPA-approved State Environmental Review
Process, EPA guidance for conducting environmental reviews, and the Clean Water Act have been
included.
3.2 Archaeological and Historic Preservation Act (54 U.S.C. § 312502)
The Archaeological and Historic Preservation Act (AHPA), also known as the Archaeological
Recovery Act and the Moss -Bennett bill, was passed and signed into law in 1974. It amended and
expanded the Reservoir Salvage Act of 1960. The AHPA built upon the national policy, set out in
the Historic Sites Act of 1935, "to provide for the preservation of historic American sites, buildings,
objects, and antiquities of national significance." The AHPA expanded the policy by focusing
attention on significant resources and data but does not require that they be shown to be of
"national" significance. The AHPA required that federal agencies provide for "...the preservation
of historical and archeological data (including relics and specimens) which might otherwise be
irreparably lost or destroyed as the result of...any alteration of the terrain caused as a result of
any Federal construction project of federally licensed activity or program.”
54 United States Code (U.S.C.) § 312502 (a)(1) states: “When any Federal agency finds, or is
notified, in writing, by an appropriate historical or archeological authority, that its activities in
connection with any Federal construction project or federally licensed project, activity, or program
may cause irreparable loss or destruction of significant scientific, prehistorical, historical, or
archeological data, the agency shall notify the Secretary, in writing, and shall provide the
Secretary with appropriate information concerning the project, program, or activity.”
54 U.S.C. § 312502 (b)(1) states: “When any Federal agency provides financial assistance by
loan, grant, or otherwise to any private person, association, or public entity, the Secretary, if the
Secretary determines that significant scientific, prehistorical, historical, or archeological data
might be irrevocably lost or destroyed, may, with funds appropriated expressly for this purpose -
(A) Conduct, with the consent of all persons, associations, or public entities having a legal
interest in the property, a survey of the affected site; and
(B) Undertake the recovery, protection, and preservation of the data (including analysis and
publication).”
The proposed collection system will be constructed primarily within existing County streets and
two short segments within private easements in the Pāhala community that have been previously
disturbed when the streets were constructed. Preliminary analysis shows the proposed treatment
and disposal facility will be constructed in an area that does not contain archaeological resources.
In 2018/2019, an Archaeological Inventory Survey (AIS), which included subsurface testing, was
conducted for the previously design of the project.. The AIS served to confirm the
presence/absence of archaeological resources on the proposed 14.9-acre site for the Pāhala
WWTP and Sewer System project. The AIS confirmed no significant artifacts or cultural deposits
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were observed on the ground surface within the Proposed WWTP Site as the area experiences
ongoing disturbance by macadamia harvesting operations and stormwater runoff. Further, no
cultural deposits or lava tubes were encountered during the subsurface trenching.
In 2023, an Archeological Literature Review Report was conducted to determine the likelihood
that historic properties may be affected by the project and, based on the findings, consider
cultural resource management recommendations. The literature review concluded that surface
pre-Contact sites are not expected within the Project Area given the known traditional land use
in this area and the impacts of continued agricultural and residential development. The modern
development of the macadamia nut orchard has likely also obliterated any plantation-era sites
once present in that part of the Project Area. Historic surface features associated with the sugar
plantation and associated village may be present. Furthermore, there is potential for pre- or post-
Contact subsurface archaeological features within the Project Area, which may or may not be
located within lava tubes. It should be noted that the literature review is intended to support the
project's historic and environmental review process; however, the report does not fulfill the
requirements of an archeological inventory survey investigation as set forth in federal and State
of Hawai'i historic preservation review requirements. For more information, please refer to
Appendix B.
The contract drawings will state that, should archaeological sites such as walls, platforms,
pavements or mounds, or remains such as artifacts, burials, concentrations of shell or charcoal
be encountered during construction activities, work shall cease immediately and the find shall be
protected from further damage. The contractor shall immediately contact the State Historic
Preservation Division (SHPD), who will assess the significance of the find and recommend an
appropriate mitigation measure, if necessary.
3.3 Bald and Golden Eagle Protection Act (16 U.S.C. § 668-668c)
The Bald Eagle Protection Act (16 U.S.C. § 668-668c) prohibits any act to take, possess, sell,
purchase, barter, offer to sell, purchase or barter, transport, export or import, at any time or in
any manner any bald eagle commonly known as the American eagle or any golden eagle, alive
or dead, or any part, nest, or egg thereof of the foregoing eagles.
No bald or golden eagles are found in Hawai‘i.
3.4 Clean Air Act (42 U.S.C. § 7401 et seq.)
Over the years, there have been a series of legislations affecting air quality and a number
amendments adopted related to air quality. The Air Pollution Control Act of 1955 was the first
federal legislation involving air pollution and was followed by the Clean Air Acts of 1963 and 1970.
The Clean Air Act of 1970 (1970 CAA, 42 U.S.C. § 7401 et seq.) authorized the development of
comprehensive federal and state regulations to limit emissions from both stationary (industrial)
sources and mobile sources.
The 1970 CAA set forth four major regulatory programs affecting stationary sources: the National
Ambient Air Quality Standards (NAAQS), State Implementation Plans (SIPs), New Source
Performance Standards, and National Emission Standards for Hazardous Air Pollutants. In Hawai‘i,
the DOH, Clean Air Branch, Air Quality program is defined by Hawai‘i Administrative Rules (HAR)
11-60.1 and serves as the SIP approved by EPA.
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The State DOH maintains 10 air monitoring stations on the island of Hawai‘i. Established in 2007,
the DOH maintains a monitoring station on the grounds of the Ka‘ū High School and Pāhala
Elementary School to monitor SO2 and PM2.5 (in terms of micrograms per cubic meter (μg/m3))
from emissions from volcanic activities.
In September 2023, the DOH issued the Annual Summary 2022 Air Quality Data report which
provides the results from the network of air quality monitoring stations. In 2022, Pahala was in
violation of the 1-hour SO2 NAAQS standard. The 2022 report stated volcanic eruptions are
considered natural events and therefore EPA may exclude the exceedances of the 1-hour NAAQS
from attainment determinations.
The quality of air in the general Pāhala area is considered "Good." The rural nature of the Pāhala
area has no major stationary sources of air pollution. Existing sources of air pollution are
emissions from motor vehicles traveling along Māmalahoa Highway and on the streets in the
community; the low level of vehicle traffic tends to limit mobile sources of emissions.
Potential short-term effects from dust and exhaust due to construction activities will be minimized
with BMPs such as water sprinkling and proper equipment maintenance. No long-term impacts
on air quality resulting from operation of the collection system, the wastewater treatment and
disposal facility, or the IWS are anticipated.
The DOH operates a network of air quality monitoring stations at various locations around the
state. In September 2023, the DOH issued the Annual Summary 2022 Air Quality Data report (the
most recent report) which provides the results from the network of air quality monitoring stations.
The DOH maintains a monitoring station on the grounds of the Ka‘ū High and Pāhala Elementary
School. Established August 2007, the station was placed to monitor SO2 and PM2.5 from volcanic
emissions. In 2022, Hawai‘i was in attainment of the state annual SO2 standard. In 2015, Hawai‘i
was in attainment with the annual NAAQS for particulate matter with a diameter of 2.5
micrometers or less (PM2.5).
Volcanic eruptions are considered natural events and therefore EPA may exclude the exceedances
of the 1-hour NAAQS from attainment determinations.
The quality of air in the general Pāhala area is considered "Good." The rural nature of Pāhala area
has no major stationary sources of air pollution. Existing sources of air pollution are emissions
from motor vehicles traveling along Māmalahoa Highway and on the streets in the community;
the low level of vehicle traffic tends to limit mobile sources of emissions.
Potential short-term effects from dust and exhaust due to construction activities will be minimized
with BMPs such as water sprinkling and proper equipment maintenance. No long-term impacts
on air quality resulting from operation of the collection system, the wastewater treatment and
disposal facility, or the IWS are anticipated.
3.5 Coastal Barrier Resources Act (16 U.S.C. § 3501)
In 1982, Congress passed the Coastal Barrier Resources Act (CBRA) (16 U.S.C. § 3501) to
minimize the loss of human life; wasteful expenditure of federal revenues; and the damage to
fish, wildlife, and other natural resources associated with the coastal barriers along the Atlantic
and Gulf coasts and along the Great Lakes by restricting future federal expenditures and financial
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assistance which have the effect of encouraging development of coastal barriers, such as federal
flood insurance through the National Flood Insurance Program.
The Coastal Barrier Resources Reauthorization Act of 2000 reauthorized the CBRA and directed
the U.S. Fish and Wildlife Service (FWS) to complete a Digital Mapping Pilot Project that includes
digitally produced draft maps for up to 75 John H. Chafee Coastal Barrier Resources System
(CBRS) areas and a report to Congress that describes the feasibility and costs for completing
digital maps for all CBRS areas.
Based on its location, the CBRA is not applicable to Hawaiʻi.
3.6 Coastal Zone Management Act (16 U.S.C. § 1451)
The Coastal Zone Management Act of 1972 (CZMA) (16 U.S.C §§ 1451-1464) was passed to
establish a national policy to preserve, protect, develop, and where possible, restore or enhance,
the resources of the Nation's coastal zone for this and succeeding generations and to encourage
coastal states to develop and implement coastal zone management (CZM) programs. Each federal
agency activity within or outside the coastal zone that affects any land or water use or natural
resource of the coastal zone shall be carried out in a manner which is consistent to the maximum
extent practicable with the enforceable policies of approved state management programs. Each
federal agency carrying out an activity subject to the Act shall provide a consistency determination
to the relevant state agency designated under § 1455(d)(6) of this title at the earliest practicable
time.
In 1977, Hawaiʻi enacted HRS 205A (Coastal Zone Management). The CZM area encompasses
the entire state, including all marine waters seaward to the extent of the state’s police power and
management authority, including the 12-mile U.S. territorial sea and all archipelagic waters. The
objective and policies of the CZM Program are set forth in HRS § 205A-2 and detailed below:
(1) Recreational Resources
Objective:
(A) Provide coastal recreational opportunities accessible to the public.
Policies:
(A) Improve coordination and funding of coastal recreational planning and management;
and
(i) Provide adequate, accessible, and diverse recreational opportunities in the coastal
zone management area by: Protecting coastal resources uniquely suited for
recreational activities that cannot be provided in other areas;
(ii) Requiring replacement of coastal resources having significant recreational value,
including but not limited to surfing sites, fishponds, and sand beaches, when such
resources will be unavoidably damaged by development; or requiring reasonable
monetary compensation to the state for recreation when replacement is not
feasible or desirable;
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(iii) Providing and managing adequate public access, consistent with conservation of
natural resources, to and along shorelines with recreational value;
(iv) Providing an adequate supply of shoreline parks and other recreational facilities
suitable for public recreation;
(v) Ensuring public recreational use of county, state, and federally owned or controlled
shoreline lands and waters having recreational value consistent with public safety
standards and conservation of natural resources;
(vi) Adopting water quality standards and regulating point and nonpoint sources of
pollution to protect, and where feasible, restore the recreational value of coastal
waters.
(vii) Developing new shoreline recreational opportunities, where appropriate, such as
artificial lagoons, artificial beaches, and artificial reefs for surfing and fishing; and
(viii) Encouraging reasonable dedication of shoreline areas with recreational value for
public use as part of discretionary approvals or permits by the land use
commission, board of land and natural resources, and county authorities; and
crediting such dedication against the requirements of section 46-6.
All project locations are at least 3.3 miles from the shoreline and, as such, the Proposed Action
will not affect coastal recreational resources under any of the Proposed Alternatives.
(2) Historic Resources
Objective:
(A) Protect, preserve and, where desirable, restore those natural and manmade historic and
prehistoric resources in the coastal zone management area that are significant in Hawaiian
and American history and culture.
Policies:
(A) Identify and analyze significant archaeological resources;
(B) Maximize information retention through preservation of remains and artifacts or salvage
operations; and
(C) Support state goals for protection, restoration, interpretation, and display of historic
resources.
Under Alternative 1 and 2, The proposed wastewater collection system will be constructed along
the existing County streets and two short segments within easements in the Pāhala community
that have been previously disturbed when the streets were constructed. Preliminary analysis
shows the treatment and disposal facility will be constructed in an area that does not contain
archaeological resources. An AIS, which included subsurface testing, was conducted to confirm
the presence or absence of archaeological resources on the proposed collection system area. The
AIS confirmed no significant artifacts or cultural deposits were observed on the ground surface
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within the Proposed WWTP Site as the area experiences ongoing disturbance by macadamia
harvesting operations and stormwater runoff. Further, no cultural deposits or lava tubes were
encountered during the subsurface trenching.
In 2023, an Archeological Literature Review Report was conducted to determine the likelihood
that historic properties may be affected any of the Proposed Alternatives and based on the
findings, consider cultural resource management recommendations. The literature review
concluded that surface pre-Contact sites are not expected within the Project Area given the known
traditional land use in this area and the impacts of continued agricultural and residential
development. The modern development of the macadamia nut orchard has likely also obliterated
any plantation-era sites once present in that part of the Project Area. Historic surface features
associated with the sugar plantation and associated village may be present. Furthermore, there
is potential for pre- or post-Contact subsurface archaeological features within the Project Area,
which may or may not be located within lava tubes. It should be noted that the literature review
is intended to support the project's historic and environmental review process; however, the
report does not fulfill the requirements of an archeological inventory survey investigation as set
forth in federal and State of Hawai'i historic preservation review requirements. For more
information, please refer to Appendix B.
The contract drawings will state that, should archaeological sites such as walls, platforms,
pavements or mounds, or remains such as artifacts, burials, concentrations of shell or charcoal
be encountered during construction activities, work will cease immediately, and the find will be
protected from further damage. The contractor will immediately contact SHPD, who will assess
the significance of the find and recommend an appropriate mitigation measure, if necessary.
(3) Scenic and Open Space Resources
Objective:
(A) Protect, preserve, and where desirable, restore or improve the quality of coastal scenic
and open space resources.
Policies:
(A) Identify valued scenic resources in the coastal zone management area;
(B) Ensure that new developments are compatible with their visual environment by
designing and locating such developments to minimize the alteration of natural
landforms and existing public views to and along the shoreline;
(C) Preserve, maintain, and, where desirable, improve and restore shoreline open space
and scenic resources; and
(D) Encourage those developments which are not coastal dependent to locate in inland
areas.
All project locations are at least 3.3 miles from the shoreline and, as such, coastal scenic and
open space resources will not be affected under any of the Proposed Alternatives.
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(4) Coastal Ecosystems
Objective:
(A) Protect valuable coastal ecosystems, including reefs, from disruption and minimize
adverse impacts on all coastal ecosystems.
Policies:
(A) Exercise an overall conservation ethic, and practice stewardship in the protection, use,
and development of marine and coastal resources;
(B) Improve the technical basis for natural resource management; \
(C) Preserve valuable coastal ecosystems, including reefs, of significant biological or
economic importance;
(D) Minimize disruption or degradation of coastal water ecosystems by effective regulation
of stream diversions, channelization, and similar land and water uses, recognizing
competing water needs; and
(E) Promote water quantity and quality planning and management practices that reflect the
tolerance of fresh water and marine ecosystems and maintain and enhance water quality
through the development and implementation of point and nonpoint source water
pollution control measures.
All project locations are at least 3.3 miles from the shoreline and, as such, coastal ecosystems
will not be adversely affected under any of the Proposed Alternatives.
(5) Economic Uses
Objective:
(A) Provide public or private facilities and improvements important to the State’s economy
in suitable locations.
Policies:
(A) Concentrate coastal dependent development in appropriate areas;
(B) Ensure that coastal dependent developments such as harbors and ports, and coastal
related development such as visitor facilities and energy generating facilities, are
located, designed, and constructed to minimize adverse social, visual, and
environmental impacts in the coastal zone management area; and
(C) Direct the location and expansion of coastal dependent developments to areas presently
designated and used for such developments and permit reasonable long-term growth
at such areas, and permit coastal dependent development outside of presently
designated areas when:
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(i) Use of presently designated locations is not feasible;
(ii) Adverse environmental effects are minimized; and
(iii) The development is important to the State’s economy.
All project locations are at least 3.3 miles from the shoreline. The collection system and the
treatment and disposal facility will be sited in suitable locations to serve the Pāhala community.
(6) Coastal Hazards
Objectives:
(A) Reduce hazard to life and property from tsunami, storm waves, stream flooding, erosion,
subsidence, and pollution.
Policies:
(A) Develop and communicate adequate information about storm wave, tsunami, flood,
erosion, subsidence, and point and nonpoint source pollution hazards;
(B) Control development in areas subject to storm wave, tsunami, flood, erosion, hurricane,
wind, subsidence, and point and nonpoint pollution hazards;
(C) Ensure that developments comply with requirements of the Federal Flood Insurance
Program;
(D) Prevent coastal flooding from inland projects.
All project locations are at least 3.3 miles from the shoreline and at least 580 feet above mean
sea level (msl). Based on the location, the Proposed Actionwill not be subject to (and will not
exacerbate) coastal hazards and do not include improvements related to tsunami, storm waves,
stream flooding erosion, subsidence and pollution under any of the Proposed Alternatives.
(7) Managing Development
Objective:
(A) Improve the development review process, communication, and public participation in
the management of coastal resource and hazards.
Policies:
(A) Use, implement, and enforce existing law effectively to the maximum extent possible in
managing present and future coastal zone development;
(B) Facilitate timely processing of applications for development permits and resolve
overlapping or conflicting permit requirements; and
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(C) Communicate the potential short- and long-term impacts of proposed significant coastal
developments early in their life cycle and in terms understandable to the public to
facilitate public participation in the planning and review process.
In December 2017, a total of five community outreach sessions were conducted in the Pāhala
community. A public information meeting for the Draft EA was held in October 2018. A total of
five community outreach sessions to discuss the Revised AOC were conducted in the Pahala and
Naalehu communities between March 2022 and September 2023. The fifth session, held on
September 28, 2023, was conducted specifically to inform the community of the preparation of
this EID and the criteria of its analysis. A recording of the meeting and the presentation slides
are available for viewing on the CoH-DEM website.
The Project Area is located at least 3.3 miles from the coast, at least 580 feet above msl, and do
not involve management of coastal resources and hazards under any of the Proposed Alternatives.
(8) Public Participation
Objective:
(A) Stimulate public awareness, education, and participation in coastal management.
Policies:
(A) Promote public involvement in coastal zone management processes;
(B) Disseminate information on coastal management issues by means of educational
materials, published reports, staff contact, and public workshops for persons and
organizations concerned with coastal issues, developments, and government activities;
and
(C) Organize workshops, policy dialogues, and site-specific mediations to respond to coastal
issues and conflicts.
In December 2017, a total of five community outreach sessions were conducted in the Pāhala
community. A public information meeting for the Draft EA was held in October 2018. A total of
five community outreach sessions to discuss the Revised AOC were conducted in the Pahala and
Naalehu communities between March 2022 and September 2023. The fifth session, held on
September 28, 2023, was conducted specifically to inform the community of the preparation of
this EID and the criteria of its analysis. A recording of the meeting and the presentation slides
are available for viewing on the CoH-DEM website.
(9) Beach Protection
Objective:
(A) Protect beaches for public use and recreation.
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Policies:
(A) Locate new structures inland from the shoreline setback to conserve open space,
minimize interference with natural shoreline processes, and minimize loss of
improvements due to erosion;
(B) Prohibit construction of private erosion-protection structures seaward of the shoreline,
except when they result in improved aesthetic and engineering solutions to erosion at
the sites and do not interfere with existing recreational and waterline activities; and
(C) Minimize the construction of public erosion-protection structures seaward of the
shoreline.
All project locations are at least 3.3 miles from the shoreline. Proposed Actiondoes not include
improvements that would affect public use beaches under any of the Proposed Alternatives.
(10) Marine Resources
Objective:
(A) Promote the protection, use, and development of marine and coastal resources to assure
their sustainability.
Policies:
(A) Ensure that the use and development of marine and coastal resources are ecologically
and environmentally sound and economically beneficial;
(B) Coordinate the management of marine and coastal resources and activities to improve
effectiveness and efficiency;
(C) Assert and articulate the interests of the State as a partner with federal agencies in the
sound management of ocean resources within the United States exclusive economic
zone;
(D) Promote research, study, and understanding of ocean processes, marine life, and other
ocean resources in order to acquire and inventory information necessary to understand
how ocean development activities relate to and impact upon ocean and coastal
resources; and
(E) Encourage research and development of new, innovative technologies for exploring,
using, or protecting marine and coastal resources.
All project locations are at least 3.3 miles from the shoreline. The Proposed Actiondoes not include
improvements that would affect development of marine and coastal resources under any of the
Proposed Alternatives.
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3.7 Endangered Species Act (16 U.S.C. § 1531)
On December 28, 1973, the Endangered Species Act (16 U.S.C. § 1531) was passed and, over
the years, has been amended a number of times. The stated purpose of the original Act was to
provide a means whereby the ecosystems upon which endangered species and threatened
species depend may be conserved, to provide a program for the conservation of such endangered
species and threatened species, and to take such steps as may be appropriate to achieve the
purposes of various related treaties and conventions. The provisions of the Act are administered
by the FWS and the National Oceanic and Atmospheric Administration (NOAA), National Marine
Fisheries Service (NMFS). The FWS has primary responsibility for terrestrial and freshwater
organisms, while NOAA/NMFS is mainly responsible for marine wildlife.
Section 7 of the Act, Interagency Cooperation (16 U.S.C. § 1536), states each federal agency
shall, in consultation with and with the assistance of the Secretary of the Interior, ensure that
any action authorized, funded, or carried out by such agency (an "agency action") is not likely to
jeopardize the continued existence of any endangered species or threatened species or result in
the destruction or adverse modification of habitat of such species which is determined, after
consultation as appropriate with affected states, to be critical, unless such agency has been
granted an exemption for such action.
In August 2018, a biological resources field survey was conducted on the 14.9-acre WWTP Site
and the collection system. The results of the survey show that, due to the proposed alignment of
the collection system along existing roadways, vegetation in the collection system area consists
entirely of maintained yards with ornamental plants.
The field survey of the 14.9-acre WWTP Site indicates that the site is comprised of a macadamia
nut orchard of mature trees, unmaintained areas outside the orchard dominated by Guinea grass,
lanes of windbreak trees oriented between orchard units, and (mostly) mowed road verge areas.
A total of 52 species of vascular plants: two ferns, one gymnosperm, and 49 species of
angiosperms (flowering plants) were identified during the survey. Only two species (4 percent)
identified during the survey are regarded as native to the Hawaiian Islands and both are
indigenous (native, but also distributed elsewhere in the Pacific). Being widely distributed
indigenous species, neither is listed as threatened or endangered or of any special concern.
The August 2018 field survey included assessment of mammalian species. With the exception of
the endangered Hawaiian hoary bat (Lasiurus cinereus semotus), or ‘ōpe‘ape‘a as it is known
locally, all terrestrial mammals currently found on the Island of Hawaiʻi are alien species, and
most are ubiquitous. The field survey reported no mammalian species within the survey area.
This also included no indication that pigs (Sus scrofa) utilize the survey area.
The field survey also included an assessment of avian species, and recorded a total of 175
individual birds of 13 species, representing nine separate families, during station counts. Avian
diversity and densities were very low, in keeping with the current usage of the site as a mature
macadamia nut orchard, with minimal ground cover and few weedy or shrubby species. All of the
avian species recorded during the course of the survey are established alien species. No native
avian species were recorded during the course of the survey. The field survey recorded no species
of plants or animals currently listed or proposed for listing under either the federal or State of
Hawai‘i endangered species statutes.
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On December 21, 2018, the designated non-federal representative for consultations under Section
7 of the Endangered Species Act, on behalf of EPA and the County of Hawaiʻi, requested
concurrence from the FWS that the Pāhala LCC Replacement Project is not likely to adversely
affect federally listed threatened and endangered species or critical habitat located within the
Project Area.
On February 15, 2019, the FWS provided a letter that concluded: "The Service has analyzed
potential impacts to listed species due to the implementation of [the] project. Based on the
inclusion of the avoidance and minimization measures listed above, the Service anticipates that
any potential impacts will be discountable or insignificant and therefore we concur that the Pāhala
LCC Replacement Project may affect, but is not likely to adversely affect the endangered Hawaiian
hoary bat, Hawaiian Hawk, Hawaiian goose, Hawaiian Petrel, Band-rumped Storm-Petrel,
Hawaiian Stilt, and Hawaiian Coot, and the threatened Newell’s Shearwater” (See Appendix C-1
of the FEA). The Proposed Action will incorporate the avoidance and minimization measures cited
in the FWS letter, including (but not limited to) avoiding impacts to potential Hawaiian hoary bat
habitat during the bat birthing and pup rearing season; conducting a Hawaiian hawk nest survey
prior to any work during the nesting season; avoiding activities near active nests; and avoiding
nighttime construction during the seabird fledging period.
3.8 Environmental Justice Executive Order 12898
Executive Order 12898, Environmental Justice (full title Federal Actions to Address Environmental
Justice to Minority and Low Income Populations), was signed on February 11, 1994. The intent
of Executive Order 12898 is to avoid disproportionately high adverse human health or
environmental effects of projects on minority and low income populations. Executive Order 12898
also requires federal agencies ensure that minority and low-income communities have adequate
access to public information related to health and the environment.
The 2021 American Community Survey (ACS) (5-Year Estimates) is the most recent information
related to socioeconomic conditions in the state and County. The 2021 ACS includes Hawai‘i
Geographic Area Profiles – Census Designated Places: Neighbor Islands. The ACS noted it is the
Census Bureau's Population Estimates Program that produces and disseminates the official
estimates of the population for the nation, states, counties, cities and towns and estimates of
housing units for states and counties.
For purposes of this assessment, and to correspond with the available ACS demographic
characteristics data, “low income” is defined as having a household income of less than $24,999;
“minority” is defined as any race population other than White; and “children” is defined as the
“Under 5 to 19” age category.
Pāhala has more households in the “less than $24,999” income bracket (25.0 percent) than the
County as a whole (18.9 percent).
Overall, Pāhala is characterized by a racial composition that includes a greater proportion of
minorities ( 82.4 percent non-White) than the County at large (67.4 percent non-White). The
racial distribution includes a much lower proportion of White residents, a much higher proportion
of Filipino residents, and lower populations of other minority groups, including Native Hawaiians
when compared to the County. There are also more residents of two or more races in Pāhala
than in the County.
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Pāhala has a similar age distribution to Hawai‘i County, although Pāhala has a higher proportion
of individuals in the “Under 5 to 19” age category (33.0 percent) compared to the County as a
whole (23.6 percent).
Based on the above, Pāhala has a higher proportion of low-income, minority, and children
residents as compared to the County as a whole. However, the Proposed Actionwill not result in
disproportionately high and adverse human health or environmental effects on these sensitive
populations under any of the Proposed Alternatives. The design and location of the WWTP facility
will minimize odor and air quality impacts. Construction of the wastewater collection system will
result in intermittent and unavoidable noise from construction vehicles and equipment within the
Pāhala community, including noise associated with the removal of bedrock. However, construction
activities within the community will comply with provisions of HAR 11-46 (Community Noise
Control). This includes obtaining a noise permit for any activities that will generate noise
exceeding the permissible sound levels specified in HAR 11-46. The permit will limit excessive
noise sources to daytime hours; will require the use of best available control technology to control
noise levels from excessive noise sources; and will require the applicant to notify affected
members of the public in advance of any planned nighttime construction activity (which must not
exceed the permissible sound levels). Overall, the Proposed Actionis expected to result in positive
human health and environmental effects to Pāhala residents by providing a cleaner and longer-
lasting wastewater treatment system.
3.9 Farmland Protection Policy Act (7 U.S.C. § 4201)
The Agriculture and Food Act was passed in 1981 and contained the Farmland Protection Policy
Act (FPPA) (7 U.S.C. § 4201). The stated purposes of the FPPA are to: 1) minimize the extent to
which federal programs contribute to the unnecessary and irreversible conversion of farmland to
nonagricultural uses; and 2) assure that federal programs are administered in a manner that, to
the extent practicable, will be compatible with state, unit of local government, and private
programs and policies to protect farmland. “Farmland” subject to FPPA requirements does not
have to be currently used for cropland.
The FPPA is administered by the U.S. Department of Agriculture (USDA), National Resources
Conservation Service (NRCS). “Farmland”, as used in the FPPA, includes prime farmland, unique
farmland, and land of statewide or local importance, as defined by the State of Hawai‘i
Department of Agriculture.
Per the Agricultural Lands of Importance to the State of Hawai‘i (ALISH) Classification System,
the collection system is located in “unclassified” lands and the proposed WWTP package plant
and effluent disposal facility will be located on approximately 20 percent “prime”, 40 percent
“other” and 40 percent “unclassified” land.
Under Alternatives 1 and 2, The proposed collection system will be located primarily within the
streets and shoulders in Pāhala and therefore will not affect farmlands. The 14.9-acre WWTP
package plant and effluent disposal facility is located within an existing macadamia nut orchard.
The 2012 Census Agriculture shows about 17,378 acres in the County are planted with macadamia
nuts. As such, the removal of the 14.9-acre area required for the Pāhala WWTP Site will not
significantly affect macadamia nut production in the state or the County. Additionally, the
construction of the IWS under Alternatives 3 and 4 would occur on a total of 174 residential lots
and would not affect macadamia nut production in the state or the County.
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In accordance with the implementation procedures for the FPPA site assessment criteria (7 CFR
658), EPA is coordinating with the local NRCS field office to complete a Farmland Conversion
Impact Rating Form for the Pāhala LCC Closure Project. This form is used to assess the potential
adverse effects on the protection of farmland; support the consideration of alternative actions;
and assess compatibility with state and local programs and policies to protect farmland. After the
alternative is selected, EPA will finalize the document and provide a copy of the form to the NRCS
field office in accordance with 7 CFR 658.4(g).
3.10 Fish and Wildlife Coordination Act (16 U.S.C § 661)
The Fish and Wildlife Coordination Act (16 U.S.C § 661), enacted on March 10, 1934, was
amended on August 12, 1958. The purpose of the Act is to recognize the vital contribution of
wildlife resources to the Nation, the increasing public interest and significance, and to provide
that wildlife conservation shall receive equal consideration and be coordinated with other features
of water-resource development programs through the effectual and harmonious planning,
development, maintenance, and coordination of wildlife conservation. The Act defines wildlife and
wildlife resources as birds, fishes, mammals and all other classes of wild animals, and all types of
aquatic and land vegetation upon which wildlife is dependent (16 U.S.C. § 666b).
The Secretary of the Interior is authorized (1) to provide assistance to, and cooperate with,
federal, state, and public or private agencies and organizations in the development, protection,
rearing, and stocking of all species of wildlife, and their habitat; in controlling losses of the from
disease or other causes; in minimizing damages from overabundant species; and in providing
public shooting and fishing areas, including easements across public lands; (2) to make surveys
and investigations of the wildlife of the public domain, including lands and waters acquired or
controlled by any agency; and (3) to accept donations of land and contributions of funds in
furtherance of the purposes of the Act.
Specifically, the Act states that “whenever the waters of any stream or other body of water are
proposed or authorized to be impounded, diverted, the channel deepened, or the stream or other
body of water otherwise controlled or modified for any purpose whatever, including navigation
and drainage, by any department or agency of the United States, or by any public or private
agency under Federal permit or license, such department or agency first shall consult with the
United States Fish and Wildlife Service” (16 U.S.C. § 662(a)). The consultation may result in a
report of recommendations by FWS that should be adopted to prevent the loss of or damage to
wildlife resources. The provisions of the Act do not apply to impoundments of water less than 10
acres.
The Proposed Actiondoes not include any impoundment of water and therefore a Fish and Wildlife
Coordination Act review and/or consultation pursuant to 16 U.S.C. § 662 is not required under
any of the Proposed Alternatives.
3.11 Floodplain Management (Executive Order 11988, as amended by Executive Orders
12148 and 13690)
Executive Order 11988, Floodplain Management, dated May 24, 1977 requires federal agencies
to avoid, to the extent possible, the long- and short-term adverse impacts associated with the
occupancy and modification of floodplains and to avoid direct and indirect support of floodplain
development wherever there is a practicable alternative.
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In accomplishing this objective, "each agency shall provide leadership and shall take action to
reduce the risk of flood loss, to minimize the impact of floods on human safety, health, and
welfare, and to restore and preserve the natural and beneficial values served by floodplains in
carrying out its responsibilities.”
The Proposed Actionis not located within a 100-year floodplain area, will incorporate stormwater
BMPs to manage runoff in accordance with state requirements, and will be designed to ensure
sufficient capacity for assimilation of peak effluent flow rates and precipitation from the design
storm event. The Proposed Actiontherefore will not have an adverse impact on floodplains and
will minimize the risk of flood-related impacts on surrounding properties under any of the
Proposed Alternatives.
3.12 Magnuson-Stevens Fishery Conservation and Management Act (16 U.S.C. § 1801)
The 1996 Sustainable Fishery Act amendments to the Magnuson-Stevens Fishery Conservation
and Management Act and subsequent Essential Fish Habitat (EFH) Regulatory Guidelines (NOAA,
2002) describe provisions to identify and protect habitats of federally managed marine and
anadromous fish species. Under the various provisions, federal agencies that fund, permit, or
undertake activities that may adversely affect EFH are required to consult with the NMFS.
Congress defines EFH as “those waters and substrate necessary to fish for spawning, breeding,
feeding, or growth to maturity.” EFH is further defined by the existing regulations (NOAA-NMFS,
2007; NOAA, 2002). “Waters” include aquatic areas and their associated physical, chemical, and
biological properties that are used by fish and may include aquatic areas historically used by fish
where appropriate; “substrate” includes sediment, hard bottom, structures underlying the waters,
and associated biological communities; “necessary” means the habitat required to support a
sustainable fishery and the managed species’ contribution to a healthy ecosystem; and
“spawning, breeding, feeding, or growth to maturity” covers a species’ full life cycle.
All project locations are at least 3.3 miles from the shoreline. The Proposed Actionwill not
adversely impact EFH under any of the Proposed Alternatives.
3.13 Marine Mammal Protection Act (16 U.S.C. §§ 1361 et seq.)
The Marine Mammal Protection Act (MMPA) (16 U.S.C. §§ 1361 et seq.), protects all marine
mammals. The MMPA includes a general moratorium on the taking and importing of marine
mammals, and prohibits, with certain exceptions, the “take” of marine mammals in U.S. waters
and by U.S. citizens on the high seas, and the importation of marine mammals and marine
mammal products into the U.S. Jurisdiction for MMPA is shared by the FWS and NMFS. The FWS
Branch of Permits is responsible for issuing take permits when exceptions are made to MMPA.
Under the exception for incidental taking, the FWS or the NMFS must find that the total taking
over the five-year period will have a “negligible impact” and will not adversely affect the
availability of the marine mammal species or stock for subsistence use by natives.
All project locations are at least 3.3 miles from the shoreline. The Proposed Actionwill not
adversely impact marine mammal communities and will not encourage any “take” of marine
mammals under any of the Proposed Alternatives
.
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3.14 Migratory Bird Treaty Act (16 U.S.C. §§ 703 et seq.)
The Migratory Bird Treaty Act (MBTA) and Executive Order 13186 (Responsibilities of Federal
Agencies to Protect Migratory Birds) provide for the protection of migratory birds. The MBTA of
1918, as amended (16 U.S.C. §§ 703-712) makes it unlawful to, among other things, pursue,
hunt, take, capture, kill, transport or import any species listed under the Act. The Act implements
conventions between the U.S., Great Britain, Mexico, Japan, and the former Soviet Union.
Executive Order 13186 was issued to assist federal agencies with their efforts to comply with the
MBTA. It should be noted that the Executive Order does not constitute any legal authorization
that in any way supersedes the requirements outlined in the MBTA. The Executive Order directs
federal agencies undertaking actions that have or are likely to have a measurable adverse impact
on migratory bird populations to develop and implement a Memorandum of Agreement with the
FWS addressing the conservation of these populations.
The initial field survey at the collection system and the 14.9 acre WWTP site found a total of 175
individual birds of 13 species, none of which are native to the Hawaiian Islands. Avian diversity
and densities were very low, which is consistent with the current site use as a mature macadamia
nut orchard with limited ground cover and few weedy or shrubby species. The field survey did
indicate that endemic Hawaiian Petrel (Pterodroma sandwichensis) and Newell’s Shearwater
(Puffinus newelli) have been recorded flying over the general area between April and the end of
November each year. Impact avoidance and minimization measures will be implemented,
including down-shielding of lights and avoiding nighttime construction during the seabird fledging
period. The Proposed Actionwill also avoid impacts to potential Hawaiian hoary bat habitat (woody
plants greater than 15 ft tall) during the bat birthing and pup rearing season (June 1 through
September 15), which in turn will also reduce the potential take of migratory birds due to tree
clearing during that period.
A secondary field survey of the Project Area in 2023 noted that one additional species, the
Hawaiian Hawk (Buteo solitarius) was recorded as an incidental observation. It is
recommended that a nesting hawk survey be conducted by a qualified biologist within three
days that any large stature trees are trimmed or felled to ensure that no active nest is
disturbed. It is presently unclear if any such action will occur as part of this Project.
3.15 National Historic Preservation Act (54 U.S.C. § 300101)
The National Historic Preservation Act (NHPA) of 1966 (54 U.S.C. § 300101) requires a federal
agency undertaking an action/project consider of the effect of the project on any historic property
defined as a district, site, building, structure, or object that is included in or eligible for inclusion
in the National Register of Historic Places.
Section 106 of the NHPA (54 U.S.C. § 306108) requires a federal agency having direct or indirect
jurisdiction over a federal or federally assisted undertaking to take into account the effect of the
undertaking on any historic property. An “undertaking” includes a “project, activity, or program
funded in whole or in part under the direct or indirect jurisdiction of a Federal agency” (54 U.S.C.
§ 300320). Because the Pāhala LCC Replacement Project will be funded using federal funds, it is
considered an “undertaking” and is subject to the NHPA.
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The Act requires the federal agency’s preservation-related activities to be carried out in
consultation with other federal, state, and local agencies, Indian tribes, Native Hawaiian
organizations (54 U.S.C § 306102).
The proposed collection system will be constructed along the existing County streets and two
short segments within private easements in the Pāhala community that have been previously
disturbed when the streets were constructed. Preliminary analysis shows the proposed treatment
and disposal facility will be constructed in an area that does not contain archaeological resources.
An AIS, which included pedestrian surveys and subsurface testing, was conducted to confirm the
presence or absence of archaeological resources on the 14.9-acre WWTP Site and Collection
System Area. Based on the AIS, no properties eligible for inclusion on the National Register of
Historic Places are present within the area of potential effects for the 14.9-acre WWTP Site and
Collection System Area, and no significant artifacts or cultural deposits on the ground surface and
no cultural deposits or lava tubes were encountered during subsurface testing.
Based on the above and in accordance with 36 CFR § 800.4(d), EPA reached a finding of “no
historic properties affected for the project or undertaking.” On September 26, 2019, EPA sent a
letter to SHPD to document their determination that no historic properties will be affected by the
undertaking and to request concurrence from SHPD. The potential for encountering unexpected
archeological resources within the Proposed WWTP Site is low due to historical ground
modifications and ongoing harvesting activities; however, the Proposed Actionwill incorporate
appropriate mitigation measures should archeological resources be discovered during
construction. Specifically, the contract drawings will state that, should archaeological sites such
as walls, platforms, pavements or mounds, or remains such as artifacts, burials, concentrations
of shell or charcoal be encountered during construction activities, work will cease immediately
and the find will be protected from further damage. The contractor will immediately contact SHPD,
who will assess the significance of the find and recommend appropriate mitigation measures, if
necessary.
As part of previous Environmental Assessment efforts, the County conducted an AIS of the 14.9-
acre treatment and disposal facility, including subsurface testing of the effluent disposal area. To
carry out this AIS, SHPD approved an AIS plan. To meet this requirement, the County submitted
the AIS plan to SHPD on March 22, 2018. On April 25, 2018, SHPD requested clarification, and
responses, including findings from the 2016 field survey report and a map of the proposed
wastewater treatment and disposal facility, were submitted to SHPD on July 31, 2018. SHPD
approved the AIS plan on August 20, 2018, and the County conducted the AIS of the 14.9-acre
WWTP in September 2018.
In addition to the AIS, the County is obligated to comply with the National Historic Preservation
Act (NHPA). On March 29, 2018, the County initiated consultation for this project in accordance
with Section 106 of the NHPA. Consultation letters were sent to various Native Hawaiian
Organizations, totaling 15 letters, inviting comments from organizations that may attach religious
or cultural significance to properties affected by the proposed actions. A letter dated February 20,
2020 from the SHPD provides concurrence that no historic properties at the Proposed WWTP Site
shall be affected, under HRS 63-8 and section 106. The AIS and NHPA Section 106 consultation
correspondence can be found in Appendix D and Appendix D-1 of the FEA, respectively.
As NHPA requirements have been completed under Alternatives 1 and 2, it is advised that the
County seek to consult with SHPD in regards to Alternatives 3 and 4 in accordance with HRS
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Chapter 6E requirements, and in relation to Section 106 of the National Historic Preservation Act
(NHPA) – if triggered – and, to incorporate additional impact avoidance and minimization
measures if required for the construction of the IWS.
3.16 Protection of Wetlands (Executive Order 11990 (1977), as amended by Executive Order
12608 (1997))
Executive Order 11990, Protection of Wetlands, dated 1977 requires federal agencies to avoid,
preserve, or mitigate effects of new construction projects on lands which have been designated
wetlands. Executive Order 11990 states in order to avoid to the extent possible the long- and
short-term adverse impacts associated with the destruction or modification of wetlands and to
avoid direct or indirect support of new construction in wetlands wherever there is a practicable
alternative, it is hereby ordered as follows: Section 1. (a) Each agency shall provide leadership
and shall take action to minimize the destruction, loss or degradation of wetlands, and to preserve
and enhance the natural and beneficial values of wetlands in carrying out the agency's
responsibilities for (1) acquiring, managing, and disposing of federal lands and facilities; and (2)
providing federally undertaken, financed, or assisted construction and improvements; and (3)
conducting federal activities and programs affecting land use, including but not limited to water
and related land resources planning, regulating, and licensing activities.
The National Wetlands Inventory (NWI) Wetlands Mapper and U.S. Geological Survey (USGS)
topographic maps identify no wetland features or streams within the Proposed WWTP Site, at the
two LCCs, or within the Proposed Collection System Area. Biological and archeological field survey
reports do not indicate any standing water or evident wetland vegetation within the area. On
August 2018, a biological field survey was conducted at the 14.9-acre WWTP Site and results of
the field work indicated that no wetlands were observed on the site (See Appendix C of the FEA).
The man-made drainage feature along Māmalahoa Highway along the edge of the parcel conducts
flow generated from surface runoff underneath the highway and downslope to the east.
Conditions within the ditch itself close to or on the 14.9-acre project site will not likely satisfy the
hydric soil requirement to be defined as a wetland. Streams in the Pāhala area do not flow all the
way to the sea, but terminate on Keone‘ele‘ele Flat to the southwest. Based on this information,
the Proposed Actionis not expected to impact wetland resources under any of the Proposed
Alternatives.
3.17 Rivers and Harbors (33 U.S.C. § 403)
Originally enacted on March 3, 1899, the Rivers and Harbors Appropriation Act of 1899 affects
navigable waters of the U.S. Section 10 of the Act states the creation of any obstruction not
affirmatively authorized by Congress, to the navigable capacity of any of the waters of the United
States is prohibited; and it shall not be lawful to build or commence the building of any wharf,
pier, dolphin, boom, weir, breakwater, bulkhead, jetty, or other structures in any port, roadstead,
haven, harbor, canal, navigable river, or other water of the United States, outside established
harbor lines, or where no harbor lines have been established, except on plans recommended by
the Chief of Engineers and authorized by the Secretary of the Army; and it shall not be lawful to
excavate or fill, or in any manner to alter or modify the course, location, condition, or capacity
of, any port, roadstead, haven, harbor, canal, lake, harbor or refuge, or enclosure within the
limits of any breakwater, or of the channel of any navigable water of the United States, unless
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the work has been recommended by the Chief of Engineers and authorized by the Secretary of
the Army prior to beginning the same (33 U.S.C. § 403).
All project locations are at least 3.3 miles from the shoreline. The Pāhala WWTP package plant
and effluent disposal facility is situated about 1,500 feet east of the center line of Hi‘onamoa
Gulch. The USGS topographic map shows the gulch stops about 5,500 feet from the shoreline.
The Proposed Actionwill not affect any streams or gulches. Based on this, Proposed Actionwill not
affect navigable waters under any of the Proposed Alternatives.
3.18 Safe Drinking Water Act (42 U.S.C. § 300f)
The Safe Drinking Water Act (SDWA) of 1974 (42 U.S.C. § 300f) was established to protect the
quality of all waters actually or potentially designed for drinking use from both underground and
aboveground sources. The SDWA authorizes EPA to establish minimum standards to protect
potable water with which all owners or operators of public water systems must comply; to oversee
the agencies which can be approved to implement these rules on EPA's behalf, such as state
governments; and to encourage attainment of secondary standards (nuisance-related). Section
1424(e) of the SDWA of 1974 (Public Law 93-523, 42 U.S.C. 300 et. seq also established the Sole
Source Aquifer program which states that no commitment for federal financial assistance (through
a grant, contract, loan guarantee, or otherwise) may be entered into for any project which the
EPA Administrator determines may contaminate such aquifer through a recharge zone so as to
create a significant hazard to public health.
The Proposed Actiondoes not establish a drinking water system, and no Sole Source Aquifers are
present on the Island of Hawai‘i. The Proposed Actionwill provide the infrastructure necessary to
enable the County to comply with the SDWA by replacing the existing outdated and federally
banned wastewater systems that pose a threat to underground sources of drinking water.
3.19 Wild and Scenic Rivers Act (16 U.S.C. §§ 1271-1287)
The Wild and Scenic Rivers Act, 16 U.S.C. §§ 1271-1287, declares that certain selected rivers with
their immediate environments, which possess outstandingly remarkable scenic, recreational,
geologic, fish and wildlife, historical, cultural, or other similar values, shall be preserved in their
free-flowing condition for the enjoyment of present and future generations. The State of Hawai‘i
has no designated wild and scenic rivers.
The Wild and Scenic Rivers Act is not applicable to this project.
3.20 Clean Water Act (33 U.S.C. § 1251 et seq.)
The Clean Water Act established the basis for regulating discharges of pollutants into waters of
the U.S. Enacted in 1948, it was originally called the Federal Water Pollution Control Act but
became known as the Clean Water Act with the amendments of 1972. Section 404 of the Clean
Water Act regulates the discharge of dredged or fill material into waters of the U.S. and adjacent
wetlands from development, water resource projects, mining or other infrastructure projects.
Activities are regulated through a permit process that is administered under the responsibility of
the U.S. Army Corps of Engineers. Permits may be issued as either Individual Permits for projects
with potentially significant impacts or general permits for projects with only minimal adverse
effects.
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The NWI Wetlands Mapper and USGS topographic maps identify no wetland features or streams
within the WWTP Site, at the two LCCs, within the Proposed Collection System Area, or within
the future IWS lots. Biological and archeological field survey reports do not indicate any standing
water or evident wetland vegetation within the WWTP Site and Collection System Area. On August
2018, a biological field survey was conducted for the proposed WWTP and collection system and
results of the field work indicated that no wetlands were observed on the site. The man-made
drainage feature along Māmalahoa Highway along the edge of the parcel conducts flow generated
from surface runoff underneath the highway and downslope to the east. Conditions within the
ditch itself close to or on the property would not likely satisfy the hydric soil requirement to be
defined as a wetland.
Because no wetland resources are present and no impacts to wetlands are anticipated due to the
nature and design of the WWTP and collection, a Clean Water Act Section 404 permit is not
required.
In addition to the above, the Clean Water Act was amended by the Federal Water Quality Act of
1987 which established provisions for a Clean Water State Revolving Fund (33 U.S.C. § 1383), a
financial assistance program for water infrastructure projects. The program capitalizes on a
partnership between EPA and states to provide loans to eligible recipients through state programs
that act as environmental infrastructure banks providing low-interest loans. As stated in Section
2.1.2, the Pāhala LCC Replacement Project is being funded in part by the State of Hawaiʻi DOH
Clean Water State Revolving Fund.
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4.Existing Environment, Impacts, and Mitigation Measures
4.1 Climate
Climate on the Island of Hawai‘i and more broadly throughout the state can be characterized as
having low day-to-day and month-to-month variability. Differences in the climate of various areas
are generally attributed to local differences in geology and topography that create microclimates
with different temperature, humidity, wind, and rainfall, and associated local ecosystems
(Department of Geography, 1998).
The climate of Pāhala is typical of the predominantly dry condition found in the Kaʻū District. The
National Oceanic and Atmospheric Administration (NOAA) designates the Kaʻū area as a Humid
Tropical Zone with transitional lowland areas in locations between windward and leeward regions.
The area receives less orographic rainfall since it is not oriented normal to trade wind flow and
exhibits a distinctive summer dry season.
Temperatures in the Kaʻū District generally range between 70 and 80 degrees Fahrenheit during
daylight hours and between 60 and 70 degrees Fahrenheit during night hours. The National
Weather Service maintains a rainfall gauge at Pāhala.
Prevailing trade winds in the Kaʻū District area are from the southeast and usually dominate from
April to November. Wind speeds average about 15 miles per hour and vary between
approximately 10 to 20 miles per hour. Winds from the southwest occur less frequently, mainly
during the winter associated with “Kona” storms (Department of Geography, 1998).
Climate conditions in the Kaʻū District are most likely to change in coming decades. Average
annual precipitation is also likely to change, but climate models are undertain in projections for
Hawaiʻi. Based on ensemble model projections available through the U.S. Environmental
Protection Agencyʻs (EPAʻs) Climate Resilience Evaluation and Awareness Tool (CREAT) Climate
Scenarios Projection Map, Projections for the area surrounding the Pāhala range from a minor
decrease in annual precipitation to up to considerable increases in annual precipitation by 2060,
depending on the model scenario (hot/dry vs. warm/wet). Other climate concerns include sea
level rise to coastal areas.
Impacts and Mitigation Measures:
Alternatives 1 and 2 - Package Plant:
Under these alternatives, the construction phase may result in temporary greenhouse gas
emissions due to heavy equipment operations and the transportation of supplies to the
WWTP project site and along the streets for the new collection system. However, these
emissions will be temporary during the construction period.
Regarding long-term climate impacts, the project's wastewater treatment and disposal
facility does not discharge to surface water sources, and therefore, it is unlikely to
significantly affect local temperature or precipitation patterns. Climate models suggest
some variability in precipitation, but this is not expected to be substantially influenced by
the project.
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The project's design takes into consideration the potential for increased storm intensity
due to climate change. Berms will be constructed at the 14.9-acre WWTP project site to
contain stormwater during intense weather events, ensuring the facility's resilience to
changing storm patterns.
Alternatives 3 and 4 - Individual Wastewater System Program:
Alternatives 3 and 4 involves the implementation of an IWS Maintenance Contract Model
or Operating Permit model. This alternative would require construction activities on
individual parcels including measures to contain storm water runoff during storm events.
The climate impacts are like those in Alternatives 1 and 2, with the project not significantly
affecting local climate conditions. The design includes measures to address potential
changes in storm intensity, ensuring the facility's resilience.
No-Action Alternative:
Under the No-Action Alternative, the existing LCCs continue to operate without any
modifications. These LCCs are at risk of impacts due to climate change, specifically
changes in precipitation patterns, increased storm intensity, and potential sea level rise.
Climate change-related impacts on the existing LCCs could result in risks to groundwater
and surface water quality. Increased storm intensity and altered precipitation patterns
may exacerbate the challenges of managing wastewater in these LCCs, potentially leading
to overflows or groundwater contamination.
It is important to note that the No-Action Alternative does not involve any mitigation
measures to address these climate-related risks.
4.2 Physiography
4.2.1 Topography
The Pāhala community is situated on the slope of Mauna Loa, located west (mauka) of Māmalahoa
Highway. The community encompasses an area of approximately 0.61 square miles. The
developed region of Pāhala exhibits a gradual slope, sloping at approximately 6 percent from the
northwest to the southeast. The community spans from an elevation of 1,000 feet above mean
sea level (msl) to 800 feet above msl, covering a horizontal distance of roughly 3,500 feet.
The streets within the community are designed to conform to the natural contours of the terrain,
maintaining level or appropriately sloped grades to facilitate vehicular travel. Consequently, on
certain streets, residential lots on the downhill side of the road are situated several feet below
the road surface, while those on the uphill side are elevated several feet above it.
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The existing topography in Pāhala is characterized by these gently sloping to moderately steep
terrains, which play a significant role in the community's layout and land use patterns.
Impacts and Mitigation Measures:
Alternatives 1 and 2 - Package Plant:
The topographical conditions under Alternative 1 are consistent with the existing
conditions. Construction activities for the new collection system and treatment facility will
involve grading and earthwork primarily at the 4.0-acre package plant site. Erosion control
measures will be implemented to prevent soil erosion and maintain the existing of the
topographic conditions. Excavation depths of 4 to 10 feet would be needed to place the
various components of the package plant. The effluent disposal facility would require
excavation of trenches of up to 3 to 4 feet would be needed to place the drip irrigation
lines. The affected areas would be restored to approximately existing conditions.
The wastewater collection system would be constructed within the right-of way of the of
public streets plus three segments within easements. The trenches typically be about 3
feet wide and at least 6 feet deep. Due to the existing topography, several parcels may
require installations of pumps to pump the flows to the street level. Once the line is placed
in the trench, the affected area would be backfilled to restore area to existing conditions
which means minimal affect the topographic conditions of the area. Proper erosion control
measures will be implemented to prevent potential soil erosion and maintain the
topography.
Alternatives 3 and 4 - Individual Wastewater System Program:
The topography for Alternatives 3 and 4 aligns with the existing conditions in Pāhala.
Construction activities for the IWS will involve excavation for placement of the septic tank
and absorption bed. Once the tank and effluent disposal system have been put into place,
grading will be needed to restore the affected area. Adequate erosion control measures
will be implemented during construction to prevent runoff during storm events and soil
erosion and protect the existing topography of the surrounding area.
No-Action Alternative:
Under the No-Action Alternative, the existing LCCs are situated within the existing
topography. There are no modifications or construction activities associated with this
alternative, and the topography remains unchanged.
Proper erosion control measures will be implemented to minimize potential impacts on the
topography during construction activities, ensuring its preservation. Overall, the
topography in the Pāhala area is not anticipated to undergo significant alterations as a
result of the proposed project alternatives.
4.2.2 Geology
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The Island of Hawai‘i was formed by the activity of five shield volcanoes. These shield volcanoes
are Kohala (extinct), Mauna Kea (has had activity during recent geologic time), Hualalai (last
erupted in 1801), and Mauna Loa and Kilauea (both of which are still active).
The project site is situated at the eastern end of the island and on the lower, southeastern flank
of the Mauna Loa Volcano. This volcano appears to be made up of at least two huge shield
volcanoes built around two separate eruptive centers, referred to as the Mauna Loa shield. The
Mauna Loa shield has been built principally by eruptions along two rift zones that extend in a
southwest and east-northeast direction from the caldera. Rift zones are elongated areas of ground
fissures where volcanic activity such as earthquakes and volcanic eruptions are concentrated. In
contrast, few eruptions have taken place along the lower northeast rift zone.
Pāhala is situated on the slopes of Mauna Loa. The surrounding area consists of several inter-
stratified beds of volcanic ash that sit upon the exposed bedrock. The Pāhala area is known to
contain lava tubes, which often occur in many places around the Island of Hawai‘i. Generally, a
lava tube is a natural conduit or a void that forms when molten lava flows beneath the hardened
surface of a previous lava flow. When the volcanic eruption stops, and the lava drains out, a lava
tube forms in the void. Lava tubes can range in size from a few inches to more than 25 feet in
diameter. The tubes are generally not visible from the surface, and the diameter and length can
usually be identified only through subsurface probing or geophysical surveys.
Impacts and Mitigation Measures:
Alternatives 1 and 2 - Package Plant:
A geotechnical investigation of the 14.9-acre WWTP project site showed the presence of
a lava tube on a portion the plant site. However, the approximately 4.0-acre package plant
has been sited to avoid the lava tube. The effluent irrigation system would only require
relatively shallow excavation for placement of the effluent disposal lines which would not
affect the geological characteristics of this area of Pāhala.
Grading, excavating, and fill activities during construction of the WWTP package plant and
effluent disposal facility and the new collection system would occur no deeper than
approximately 10 feet below grade and thus would not have significant impacts on the
geology in the Pāhala area. If/when bedrock is encountered during excavation for the
proposed actions, removal would be accomplished using excavators or hydraulic and/or
pneumatic hammers consistent with other construction activities on the Hawaiian
Islands.Alternatives 3 and 4 - Individual Wastewater System Program:
Alternatives 3 and 4 involves the installation and maintenance of the IWS. While this
alternative may require construction activities that could disturb deeper geological layers
(possibly up to 8 to 10 feet), this depth of excavation should not affect the geology of the
Pahala area.
No-Action Alternative:
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Under the No-Action Alternative, the existing LCCs continue to operate without any
modifications. This alternative does not involve any construction activities or modification
to the existing conditions, and therefore would not cause any impacts to geology in the
Pāhala area.
4.2.3 Soils
According to the U.S. Department of Agriculture Natural Resource Conservation Service (NRCS)
Soil Survey of the island, soils types within the Pāhala area possess moderately high to high
permeability characteristics and consist of well-drained soils formed of volcanic ash. Specifically,
the area includes the following soil profiles:
• Map Unit Symbol (MUSYM) 521 – Nāʻālehu medial silty clay loam, 3 to 10 percent slopes
• MUSYM 522 – Nāʻālehu medial silty clay loam, 10 to 20 percent slopes
• MUSYM 567 – Puʻuʻeo – Nāʻālehu complex, 3 to 10 percent slopes
Impacts and Mitigation Measures:
All Proposed Alternatives
Construction of the new collection system would occur below the travelways or shoulders
of the streets in the Pāhala community. As these areas were previously distrurbed upon
construction of the streets, the collection system would not create adverse impacts to soils
in the area.
Construction of the any of the alternatives would require vegetation removal, clearing,
and excavation. These activities would involve subsurface and surface disturbance to the
soils of the affected areas. . These impacts can by mitigated through incorporating
appropriate stormwater and erosion control measures to ensure that soil erosion and
transport during construction activities are minimized. Typically, the construction plans
and documents would include erosion control plans which the construction contractor
would need to follow.
No-Action Alternative
Under the No-Action Alternative, the existing LCCs would continue to operate without any
modifications. This alternative does not involve any construction activities or modification
to the existing conditions, and therefore would not cause any impacts to soils in the Pāhala
area.
4.3 Water Resources
4.3.1 Surface Waters
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The Pāhala community is situated between two surface water sources, with Pāʻauʻau Gulch to the
north and east and an unnamed branch of Hionamoa Gulch to the south and west. According to
USGS topographic maps, the flows from Pāʻauʻau Gulch terminate about 6,500 feet from the
coast, while the unnamed branch joins Hionamoa Gulch approximately 3,000 feet southwest of
Maile Street. The flows from Hionamoa Gulch also cease about 6,000 feet from the coast.
Water resources in the area are crucial for both the existing wastewater treatment systems and
the local community. Groundwater and surface water sources play a vital role in sustaining the
environment and supporting agriculture.
According to the April 2023 PER, the DOH Wastewater Branch has assigned three-priority levels
to each of the 88,000 cesspools across the state of Hawai’i. These priority levels ranged from
Priority 1: Significant Risk of Human Health Impacts, Drinking Water Impacts, or Draining to
Sensitive Waters to Priority 4: Impacts Not Identified. Priority 1 and 2 areas would be required to
upgrade sooner and to higher levels of treatment. Under this priority classification system, the
Pāhala area fell under Priority 4, the lowest of those available, as an area for which health and
environmental risks had not been assessed or appeared low. Subsequently, a more
comprehensive 2021 study that explored Hawai‘i’s cesspool prioritization, factoring in a total of
15 risk factors, reached a similar conclusion.
Impacts and Mitigation Measures:
Alternatives 1 and 2 - Package Plant:
Under Alternative 1, construction activities may temporarily impact water resources. The
cumulative areal extent of disturbance for the wastewater treatment and disposal facility
and the new collection system would require coverage under a National Pollutant
Discharge Elimination System (NPDES) construction stormwater permit. Normally, this
permit would mandate the implementation of best management practice (BMP) measures,
such as silt fences, filter socks, and sediment traps to control sediment runoff. Since the
NPDES permit requires detail information about the means and method of construction,
the selected contractor would need to submit the plans and documents to the DOH.
Construction trenches would be designed not to extend deeper than approximately 10
feet below grade when feasible, minimizing disturbance to the geology in the Pāhala area.
It should be noted that construction trenches may need to exceed 10 feet in depth in
some design locations. A Site-Specific Construction BMP plan would be developed to
prevent stormwater runoff along the collection system during construction.
The on-site drainage plan, as per Hawai‘i County Code, Chapter 27, Section 20, would
ensure that runoff caused by the construction activities in the 14.9-acre package plant
and effluent disposal area would need to account for expected one-hour, ten-year storm
event, is retained within the site boundaries. Landscape buffers with dirt berms would act
as secondary containment during large storm events, further safeguarding against
adverse impacts on adjacent or downstream properties.
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Overall, construction-related impacts on surface water resources under Alternatives 1 and
2 are expected to be temporary, with BMPs effectively minimizing potential impacts.
Alternative 3 - Individual Wastewater System-Maintenance Contract Model:
Alternative 3 entails the implementation of an IWS Maintenance Contract Model which,
when properly designed and operated, can be an effective means of wastewater
management; however, IWS that are poorly designed and maintained have been
nationally recognized as having high failure rates. In order to ensure that the systems
function as intended, the design must take into account a variety of technical
considerations including system size, site conditions, location, subsurface soil
characteristics, influent characteristics, and level of treatment.
Should the IWS begin to fail, untreated sewage containing pathogens (e.g., E. coli),
nutrients and other harmful substances could be discharged into the groundwater or into
nearby surface waters.
In the event that the County opts to pursue the IWS Alternatives, the implementation of
BMP measures, including silt fences, filter socks, and sediment traps, would be required
during construction at each IWS site to control sediment runoff. Construction trenches
would generally not extend deeper than approximately 10 feet below grade.
Overall, construction-related impacts on surface water resources under Alternative 3 are
anticipated to be temporary and localized, with BMPs effectively minimizing potential
impacts.
Alternative 4 - Individual Wastewater System-Operating Permit to Homeowners:
Alternative 4 involves the implementation of an IWS Operating Permit model. As noted
under Alternative 3, a properly designed and operated IWS can be an effective means of
wastewater management; however, IWS that are poorly designed and maintained have
been nationally recognized as having high failure rates and have been linked to
contaminated groundwater resources. Under Alternative 4, the homeowner will be
responsible for operating and maintaining the IWS while the County is responsible for
issuing maintenance notifications to the homeowner.
Like the other alternatives, construction activities may temporarily impact water resources.
The implementation of BMP measures, including silt fences, filter socks, and sediment
traps, would be required during construction to control sediment runoff. Construction
trenches would generally not exceed approximately 10 feet below grade.
Construction-related impacts on surface water resources under Alternative 4 are expected
to be temporary and localized, with BMPs effectively minimizing potential impacts.
No-Action Alternative:
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Under the No-Action Alternative, which involves the continued operation of the existing
LCCs without modifications, there would be no construction activities or modifications to
existing conditions. Therefore, this alternative would not cause any impacts to geology or
surface water resources in the Pāhala area.
It's important to note that the No-Action Alternative does not involve any mitigation
measures to address potential stormwater-related risks associated with the existing LCCs.
4.3.2 Groundwater
Groundwater occurs within portions of geologic formations where aquifers receive and store
water. Depending on the geologic conditions of the area, many communities and areas on the
island rely on groundwater wells to obtain drinking water. To protect the quality of underground
sources of drinking water from contamination by subsurface disposal of fluids, Hawai‘i has
adopted the Underground Injection Control (UIC) program administered by the DOH Safe
Drinking Water Branch. Hawai‘i Revised Statues (HRS) 340 E and Hawai‘i Administrative Rules
(HAR) 11-23 (Underground Injection Control) set forth the requirements related to protection of
underground sources of drinking water.
Under HAR 11-62, Appendix F, a minimum separation of 1,000 feet from existing wells is required
for wastewater treatment sites.
On April 3, 2018, in response to the previously issued Draft EA pre-assessment notification, the
DOH Safe Drinking Water Branch indicated that the proposed WWTP Site is located above the
UIC line and, as such, on top of underground sources of drinking water. To avoid impacts to
drinking water wells, sewage injection wells cannot be constructed above the UIC line.
The State of Hawai‘i Department of Land and Natural Resources (DLNR) Commission on Water
Resource Management (CWRM) maintains information on various types of wells throughout the
state. The CWRM indicated that one County and one private well are located in the Pāhala area.
The CWRM confirmed that the County well and storage tank are located approximately 5,300 feet
north of the WWTP Site. The tank lies at about 1,120 feet above msl, which is approximately 480
feet higher in elevation than Pāhala WWTP site. A private well is located within TMK 9-6-002:016,
the parcel that contains the existing LCC 1 and lies adjacent to the WWTP Site. The CWRM has
indicated this well is used for agricultural purposes, not for domestic purposes.
Impacts and Mitigation Measures
Alternatives 1 and 2 - Package Plant:
The approximately 6-foot trenches needed to support the collection system would be
relatively shallow in relation to groundwater resources in the Pāhala area. Thus,
construction of the collection system would not affect groundwater resources in the area.
The separation (both elevation and horizontal distance) between the Pāhala WWTP site
and the upgradient location of the County drinking water well, would mean construction
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and operation of the treatment and disposal facility would not affect potable groundwater
resources in the Pāhala area.
While use of the two existing LCCs has not resulted in documented impacts to
groundwater or drinking water resources, abandonment of the LCCs would remove a
potential source of such impacts. Abandonment of the existing wastewater collection
system would not affect groundwater within the affected areas.
Alternative 3 and 4 - Individual Wastewater System Program:
Alternatives 3 and 4 entail the implementation of an IWS program which, when properly
designed and operated, can be an effective means of wastewater management; however,
IWS that are poorly designed and maintained have been nationally recognized as having
high failure rates. To ensure that the systems function as intended, the design must take
into account a variety of technical considerations including system size, site conditions,
location, influent characteristics, and level of treatment.
Should the IWS begin to fail, untreated sewage containing pathogens (e.g., E. coli),
nutrients and other harmful substances can be discharged into the groundwater or into
nearby surface waters.
In the event that the County opts to pursue the IWS Alternatives, the implementation of
BMP measures would be required at each site, including silt fences, filter socks, and
sediment traps to control sediment runoff.
Overall, construction-related impacts on groundwater water resources under Alternatives
3 and 4 are anticipated to be temporary and localized, with BMPs effectively minimizing
potential impacts.
No-Action Alternative:
The No-Action Alternative has the potential to adversely impact groundwater resources
due to the continued operation of the existing LCCs. EPA regulations mandate the closure
of LCCs to prevent potential impacts on groundwater resources
4.4 Agricultural Lands
On November 1965, the Land Study Bureau (LSB) at the University of Hawai‘i issued L.S. Bulletin
No. 6, Detailed Land Classification–Island of Hawai‘i. The LSB compiled and interpreted data on
geology, topography, climate, water resources, soils, and crops and conducted field investigations
to create a land classification for the island. Bulletin No. 6 assigned two types of ratings for each
land type: the overall or master productivity rating, which reflects degree of overall suitability for
agricultural use, ranging from A (Very Good) to E (Very Poor); and selected use ratings, which
indicate the degree of suitability for selected use alternatives. Bulletin No. 6 has not been revised
or re-issued and remains as the reference document for lands classified by the LSB.
In addition to the LSB rating, the State of Hawai‘i has developed the Agricultural Lands of
Importance to the State of Hawai‘i (ALISH) Classification System. This system was developed
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and compiled in 1977 by the State Department of Agriculture with assistance from the NCRS,
U.S. Department of Agriculture (formerly the Soil Conservation Service) and the College of
Tropical Agriculture at the University of Hawai‘i as part of a national effort to inventory important
farmlands. Lands not considered for classification within this system are developed urban lands
(over ten acres), natural or artificial bodies of water (over ten acres), public use lands, forest
reserves, lands with slopes in excess of thirty-five percent, and military installations (except
undeveloped areas over ten acres). The ALISH Classification System identifies the following three
categories of land (equivalent NRCS categories in parentheses):
• Prime Agricultural Lands (Prime Farmlands) – Land that has the soil quality, growing
season, and moisture supply needed to produce sustained high yields of crops
economically when treated and managed according to modern farming methods.
• Unique Agricultural Lands (Unique Farmlands) – Land that has a special combination of
soil quality, location, growing season, and moisture supply, and is used to produce
sustained high-quality yields of a specific crop when treated and managed according to
modern farming methods.
• Other Important Agricultural Land (Additional Farmland of Statewide and Local
Importance) – Land other than Prime or Unique Agricultural Land that is also of statewide
or local importance to agricultural use.
The 2017 US Census Bureau, Census of Agriculture-County Data provides the most recent
information related to acreage planted for various fruits and nuts across the state and for each
county. The 2017 data show a total of 18,170 acres of macadamia nuts were planted in the state,
with 17,504 acres planted in the County, comprising about 96.3 percent of the state total.
Impacts and Mitigation Measures
Alternatives 1 and 2 – Package Plant
The LSB rating indicates the collection system project site as “not rated”, the rating
assigned to developed communities, and a master productivity rating of “D 129” (poor)
for about 50 percent of the proposed wastewater treatment and disposal facility at the
WWTP Site, with the remainder “B” (good). D 129 includes soils from the Māmalahoa
series, deep depth, volcanic ash, stony, well drained, and very poorly suited for mechanical
agitation / tilling. The ALISH map shows the collection system is located in “unclassified”
lands. The ALISH map shows the proposed wastewater treatment and disposal facility
would be located on approximately 20 percent “prime”, 40 percent “other” and 40 percent
“unclassified” land.
Construction of the collection system within the County roads would not affect agricultural
lands or the acreage utilized for the macadamia nut orchard.
Construction of the Pāhala WWTP package plant would require removal of approximately
4.0-acres of macadamia nut trees. Although the remaining macadamia nut orchard would
not be removed, use of the trees for effluent disposal means the lands could not be used
as a productive macadamia orchard. This removal would amount to less than 0.1 percent
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of the total County lands planted with macadamia nut trees, which would not substantially
affect the total macadamia nut acreage in the state or the County.
Abandonment of the two LCCs would reduce the potential for contamination of
groundwater that is used for irrigation of agricultural lands. Otherwise, abandonment of
the LCCs and the existing wastewater collection system would not affect agricultural lands
within the affected areas.
Alternatives 3 and 4 – Individual Wastewater System Program:
As indicated by the LSB rating system, the lots identified for the IWS installation are “not
rated” which is assigned to developed communities. Installation of the IWS would not
affect agricultural lands.
No-Action Alternative
The No-Action Alternative would not impact agricultural lands. Continued operation of the
existing LCCs could introduce pathogens and other contaminants to groundwater sources
used for irrigation of agricultural lands.
4.5 Natural Hazards
The Disaster Mitigation Act of 2000, (Federal Emergency Management Agency (FEMA), 44 Code
of Federal Regulations, Hazards Mitigation Planning required States and Counties to have
approved hazard mitigation plans as of November 1, 2004 to receive Pre-Disaster Mitigation
funding. The development of State and local hazard mitigation plans is critical for maintaining
eligibility for future FEMA mitigation and disaster recovery funding.
Given Hawai‘i’s vulnerability to natural hazards and history of disasters, the State has maintained
and implemented a comprehensive, multi-hazard mitigation strategy to reduce loss of life and
property damage. This strategy is embodied in the 2018 State Multi-Hazard Mitigation Plan. This
plan identifies the major natural hazards that affect the stateʻs population, property, and
infrastructure to the specific hazard, and recommends actions that can be taken to reduce the
risk and vulnerability to the hazard. The State Hazard Mitigation Plan also contains a description
of programs, policy, statutes, and regulations applicable to hazard mitigation. It should be noted
that the 2023 update to this plan has begun and is expected to be released at the end of 2023.
Identified major natural hazards that could affect the State, as well as the County are Climate
Change Effects (including sea level rise (SLR)/coastal erosion), floods, tsunamis, strong,
windstorms/hurricanes, earthquakes, landslides/rockfalls, volcanic activity, and wildfires.
4.5.1 Sea Level Rise
Sea level is rising at increasing rates due to global warming of the atmosphere and oceans and
melting of the glaciers and ice sheets. Rising sea level and projections of stronger and more
frequent El Niño events and tropical cyclones in waters surrounding Hawai‘i indicate a growing
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vulnerability to coastal flooding and erosion. The Hawai‘i Sea Level Rise Vulnerability and
Adaptation Report (2017) modeled exposure to chronic coastal flooding and erosion using
projections from the Intergovernmental Panel on Climate Change (IPCC) 5th Assessment Report
(IPCC, 2014) where the high-end scenario was up to 3.2-ft of sea level rise by the end of the
century (Courtney et al., 2020).
Impacts and Mitigation Measures:
All Proposed Alternatives
No short- or long-term impacts are anticipated during the construction or operation of any
of the alternatives. The Pāhala community is located approximately 3.3 miles from the
nearest coastline and at elevation from 500 to 1,500 feet above Mean Sea Level (MSL).
The community is not anticipated to be impacted by sea level rise under any of the
proposed alternative.
4.5.2 Flood and Tsunami Threat
The Pāhala community is located between two surface water sources, Pāʻauʻau Gulch to the north
and east, and an unnamed branch of Hi‘onamoa Gulch to the south and west. The USGS
topographic map shows flows from Pāʻauʻau Gulch end about 6,500 feet from the coast, while
the unnamed branch flows into Hi‘onamoa Gulch about 3,000 feet southwest of Maile Street.
Flows from Hi‘onamoa Gulch end about 6,000 feet from the coast. Figure 3.1 illustrates the known
streams and gulches within the Pāhala area.
The Federal Emergency Management Agency (FEMA) Flood Insurance Rate Map (FIRM),
Community Panel No. 155166 1800F, effective date September 29, 2017, shows no special flood
hazard areas present in the Pāhala WWTP site and that most of the Pāhala area is located in
Zone X, which designates areas determined to be outside the 0.2- percent annual chance (500-
year) floodplain. A small portion of the community of Pāhala, including some land within the
collection system project site, is located within Zone X – Other Flood Areas, indicating areas within
the 0.2-percent annual chance (500-year) floodplain, or areas with a 1-percent annual chance of
flooding with average flood depths less than 1 foot.
According to the FIRM, both existing LCCs are also located within Zone X. However, LCC 1 is
very close to the edge of the 500-year floodplain.
Impacts and Mitigation Measures:
All Proposed Alternatives
Based on the above, no significant impacts on flood hazards are anticipated to occur within
the Pāhala regiion as a result of any alternative considered.
4.5.3 Hurricane and Wind Hazard
The Hawaiian Islands are seasonally affected by Pacific hurricanes from the late summer to early
winter months. The State has been affected once by the significant hurricanes (rated Category
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3 and higher) Iniki in 1992. Not all identified hurricane and strong wind storm threats make
landfall in Hawai‘i, and actual hurricane strikes in Hawai‘i are relatively rare in modern record.
More commonly, near misses that generate large swell and moderately high winds causing varying
degrees of damage are the hallmark of hurricanes passing close to the islands.
During hurricanes and storm conditions, high winds cause strong uplift forces on structures,
particularly on roofs. Wind-driven materials and debris can attain high velocity and cause
devastating property damage and harm to life and limb. Along the coastline, a surge of water,
topped by battering waves can move ashore into low lying coastal areas. Due to differences in
atmospheric pressure, tidal stage, coastal topography, and location relative to the eye of the
hurricane it is difficult to predict how hurricane‐induced storm surge may impact a specific
location. It is difficult to predict these natural occurrences, but it is reasonable to assume that
future events will occur. The Project Area is, however, no more or less vulnerable than the rest
of the island to the destructive winds and torrential rains associated with hurricanes.
Impacts and Mitigation Measures:
All Proposed Alternatives
While rare, the threat of hurricanes is present across the State of Hawaiʻi. Construction
activities could potentially exacerbate the effect of hurricanes if loose materials are not
secured prior to the event of a storm and become flying debris. To minimize this hazard,
construction materials and equipment would be stored properly when not in use,
consistent with construction best management practices.
To safeguard against hurricane damage in the long-term, proposed action improvements
would be designed in compliance with American Society of Civil Engineers and
International Building Code standards for wind exposure.
4.5.4 Seismic Hazard
Seismic hazards are those related to ground shaking. Landslides, ground cracks, rock falls and
tsunamis are all seismic hazards. Thousands of earthquakes occur every year in the State of
Hawai‘i. Earthquakes in the Hawaiian Islands are associated with volcanic eruptions or tectonic
movements. Most of these earthquakes are closely related to volcanic processes and are so small
they can only be detected by seismometers. Volcanic hazards in the area are of particular concern
given to the active status of the islands volcanoes. One of the larger and more recent earthquakes
occurred offshore of Puakō, Hawai‛i in 2006. The earthquake measured 6.7 on the Richter Scale
and caused minor damages to structures and buildings.. Although difficult to predict, an
earthquake of sufficient magnitude causing structural or other property damage may occur in the
future.
Impacts and Mitigation Measures:
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All Proposed Alternatives:
Hawai‘i County Code (HCC) § 5A indicates the “International Building Code, 2006 Edition”
(IBC) – copyrighted and published in 2018 by the International Code Council, Incorporated
– is adopted by the County. Chapter 5 is the applicable code for the construction of
buildings, structures, and facilities in the County. The purpose of the seismic provisions in
the IBC is primarily to safeguard against major structural failures and loss of life; limiting
damage or maintaining functions is not a primary purpose. At a minimum, structures are
to be designed and constructed to resist the effects of ground motions from seismic
events. The seismic hazard characteristics described in the IBC are based on the seismic
zone and proximity of the site to active seismic sources.
The proposed improvements would be designed and constructed to meet the
requirements of the 2016IBC and HCC Chapter 5 and would comply with seismic loadings
established for the County of Hawaiʻi. This would minimize the potential for an
uncontrolled release of untreated or partially treated sanitary wastewater, or diesel fuel
from the tank being held for the emergency generator during a seismic event. The County
would also develop a facility management plan in accordance with applicable rules and
regulations.
No-Action Alternative:
The No-Action Alternative includes no construction or modification to existing conditions,
and therefore would not impact seismic hazards in the Pāhala area.
4.5.5 Volcanic Hazard
The US Geologic Survey (USGS) prepared a volcanic hazard zone map for the island of Hawaiʻi
which was last updated in 1997. The map shows lava flow hazard zones for the five on-island
volcanoes. The map utilizes a 9-point ranking system which classifies zones ranked from 1
(highest hazard) thorugh 9 (lowest hazard) based on the probability of covereage by lava flows.
Pāhala area has been assigned a rating of Zone 3. This designates areas which are less hazardous
due to their distance from recently active vents. One to five percent of areas within the Zone 3
rating have been covered by eruptions since 1800, and 15 to 75 percent have been covered within
the past 750 years.
Impacts and Mitigation Measures:
All Proposed Alternatives
Based on the volcanic hazard map, the potential for damage to buildings and structures
is moderate, given the distance between the Pāhala community and active vents and
hazards. At this time, the County has no construction restrictions in Zone 3 areas. Thus,
the volcanic hazard designation would not affect the construction and operation of the
collection system or the treatment and disposal facilities. Although the potential for
volcanic activity in or around Pāhala is present, the likelihood of that impact is relatively
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small. In the event of a volcanic eruption that threatens the Pāhala area, it is likely that
damage would occur to residences, the treatment and disposal facility, the collection
system, and other assets in the area. There are no mitigation measures to prevent the
potential impacts from volcanic activity, and the impacts would be similar regardless of
the location of the treatment and disposal facility or treatment system employed.
No-Action Alternative
The No-Action Alternative includes no construction or modification to existing conditions,
and therefore would not impact volcanic hazards in the Pāhala area.
4.5.6 Wildfire Hazards
Wildfires can threaten life and property, but they can also harm the environment and threaten
important natural resources such as endangered species. While sometimes caused by lightning,
nine out of ten wildfires are human-caused. Put simply, "wildfire" is the term applied to any
unwanted and unplanned fire burning in forest, shrub or grass regardless of whether it is naturally
or human induced (DEM, 2020).
All of the Hawaiian Islands are susceptible to wildfires, especially during prolonged drought and
high winds. In recent years, the average annual cost to suppress wildfires in Hawaiʽi is about
$1,100,000 - making it a Statewide risk (DEM, 2020). The greatest danger of fire is where
wildlands borders urban areas. Through August, 2018, wildfires in Hawaiʽi have burned 30,000
acres (about double the annual average). Historically, the majority of these fires have been
directly caused by humans, either directly or by negligence. The Project Site is not located in an
at risk area for wildfires; however, the community to the north of the Project Site is noted as a
High Risk area for wildwire which may potentially impact the Project Area in the event of a wildfire
. As further evidenced by recent events in West Maui, wildfires pose a significant threat to health
and human safety, and must be taken very seriously.
Impacts and Mitigation Measures:
Alternatives 1 and 2
While the proposed alternatives are not anticipated to have impacts that could result in
wildfire events, the Pāhala area is considered to be an area that is at high risk for wildfires.
The State Department of Land and Natural Resources-Division of Forestry and Wildlife
(DLNR-DOFAW) has adopted a Fire Management Handbook, which specifies its
standards for prevention, pre-suppression, and suppression. The document provides a
structured approach in providing for public/firefighter safety and minimizing damage to
Hawaiʽi's environment. Funding for the fire management program is provided by the
State's general fund and federal cost share programs through the U.S. Forest Service.
These programs include the Rural Community Fire Protection and Rural Fire Protection
and Control programs. Additionally, the DLNR-DOFAW is a key agency within the State
who can trigger provisions of the Stafford Act (Fire Suppression Assistance), which
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provides for FEMA funding assistance in situations where forest and grass fires on public
or private lands threaten a major disaster to communities and economies.
The package plant and related facilities would be designed according to National Fire
Prevention Association (NFPA) 820 “Standard for Fire Protection in Wastewater
Treatment and Collection Facilities.” In accordance with Hawaiʻi Fire Department
requirements, Fire Department access and water supply to the proposed WWTP site
would be designed to comply with Chapter 18 of NFPA 2006 Uniform Fire Code as
amended by the County.
Alternatives 3 and 4
The IWS systems do not include construction of facilities which would be susceptible to
fire hazards.
No-Action Alternative
The No-Action Alternative includes no construction or modification to existing conditions,
and therefore would not impact wildfire hazards in the Pāhala area.
4.6 Flora and Fauna
The Pāhala community and its surrounding areas contain a variety of vascular plant species. An
initial botanical field study conducted in August 2018 at the Proposed WTTP site indicated the
presence of various plant species, including ornamental plants in maintained yards. Among the
species observed, only two species (Ipomoea indica and Waltheria indica) are regarded as native
to the Hawaiian Islands, both of which are indigenous and widely distributed. These indigenous
species are not listed as threatened, endangered, or of any special concern. Additionally, the
macadamia nut orchards in the area are valuable commercial botanical resources but are not
considered environmentally sensitive. Cook pines (Araucaria columnaris) lining Maile Street along
the western border are considered important elements of the local landscape.
In October 2023, a second botanical survey was conducted in the Project Area. This survey started
on Maile Street near the intersection with Maoula Road and proceeded along the route of the
proposed IWS lots. For the streets occupied by residential lots, the botanists walked the streets
noting the plants observable in the yards to create a separate list (of mostly landscape species)
to support a conclusion that few if any sensitive species are likely to occur on the Project Area.
Consistent with the 2018 survey, the 2023 survey indicated the presence of various plant species,
including ornamental plants in maintained yards. Among the species observed, only two species
(Ipomoea indica and Waltheria indica) are regarded as native to the Hawaiian Islands, both of
which are indigenous and widely distributed. The survey establish that listed species, indeed
native species as only were observed are unlikely to be encountered in areas subjected to
disturbance during the construction of the Proposed Action.
The general area surrounding Pāhala supports a limited range of mammalian and avian species.
An initial biological field survey conducted in August 2018 at the proposed WWTP site identified
terrestrial mammalian species, with the exception of the endangered Hawaiian hoary bat
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(Lasiurus cinereus semotus), as alien species, most of which are widespread and ubiquitous on
the Island of Hawaiʻi. The survey did not record any mammalian species within the surveyed area.
The community reported occasional use of the area for pig hunting, but there was no indication
of pig (Sus scrofa) presence during the survey.
In October 2023, a second biological field survey was conducted for the Project Area. During this
study, sign of pigs were encountered in the undeveloped area just west of the town along Maile
Street. Additionally, in 2023, the study heard and observed numerous dogs (Canis lupus familiaris)
across the neighborhood area. It is likely that one or more of the four Muridae (rats and mice)
found on the Island—roof rat (Rattus rattus), brown rat (Rattus norvegicus), Polynesian rat
(Rattus exulans hawaiiensis), and European house mouse (Mus musculus domesticus) use
resources within the general Project Area on a seasonal basis. These introduced rodents are
deleterious to native ecosystems and native faunal species.
The initial avian survey conducted in August 2018 at the Proposed WWTP site identified avian
species in the general area. The survey recorded a limited diversity of avian species, primarily
consisting of established alien species. No native avian species were recorded during the survey.
The general area occasionally witnesses the presence of endemic Hawaiian Petrel (Pterodroma
sandwichensis) and Newell’s Shearwater (Puffinus newelli) flying over, mainly between April and
the end of November each year. These seabirds are listed as endangered and threatened,
respectively, under both Federal and State endangered species statutes and are susceptible to
adverse impacts from outdoor lighting, which can lead to disorientation, fallout, and injury or
mortality.
The second avian survey conducted in 2023 identified total of 129 individual birds of 14 species,
representing 10 separate families, was recorded during station counts. One additional
species, Hawaiian Hawk (Buteo solitarius) was recorded as an incidental observation. The
remaining 14 species recorded are commonly encountered established introduced species.
The avian diversity and densities observed during the surveys are consistent with the habitats
present in the area and usage of the properties. Four species—House Sparrow (Passer
domesticus), Zebra Dove (Geopilia striata), Northern Cardinal (Cardinalis cardinalis), and
Japanese White-eye (Zosterops japonicus)—accounted for 44% of all birds recorded during
station counts over the course of the two surveys. The most frequently recorded species was
House Sparrow, which accounted for 12% of the total number of individual birds recorded
during station point-counts.
It is possible that the endangered Hawaiian hoary bat (Lasiurus semotus) uses resources
within the Project vicinity. This bat is regularly seen in the Project area (David, 2023) and tall
trees suitable for roosting are present here. This bat species is solitary and rare but with a
widespread distribution on Hawai‘i. Island. However, the bat uses multiple roosts within a
home territory (Bonaccorso, 2015), so the disturbance associated with removal of any
particular tree would be minimal. An exception might be during the pupping season if a
female bat carrying a pup or an unattended pup is in a tree being felled, these individuals
could be unable to flee the tree.
Impacts and Mitigation Measures:
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All Proposed Alternatives:
Based on the findings of the botanical and biological field surveys, construction activities
associated with the new collection system and wastewater treatment and disposal facility
are not anticipated to result in adverse impacts to botanical and faunal resources in the
Pāhala area.
The operations building in the 4.0-acre package plant will feature down-shielded light
fixtures to minimize the potential for adverse impacts on avian species.
Prior to finalization of this EID and the selection of a preferred alternative for
implementation by DEM, the DOH will conduct , consultation with the U.S. Fish and Wildlife
Service (FWS) pursuant to Section 7 of the Endangered Species Act should it be necessary.
Additional impact avoidance and minimization measures recommended by FWS would
consequently be incorporated in accordance with Section 7 Consultation.
It should be noted that for Alternatives 3 and 4, the area of disturbance for the proposed
action will take place on private residential property. However, it is expected that
Alternatives 3 and 4 will result in no impacts to botanical and faunal resources.
Generally speaking, minimization measures discussed herein are intended to minimize any
potential impacts on flora and fauna that could result from the construction and operation
of the wastewater treatment and disposal facility and associated infrastructure. The
proactive consultation with relevant authorities ensures compliance with regulations and
protection of sensitive species. Additionally, the note regarding Alternatives 3 and 4
acknowledges the unique context of disturbance on private residential property while
anticipating minimal impacts.
Seabirds
• The Project can minimize or avoid risks to protected night-flying seabirds by not
conducting night-time construction and ensuring that all associated outdoor lighting is
fully shielded (Night sky compliant; HDLNR-DOFAW, 2016).
Hawaiian Hawk
• It is recommended that a nesting hawk survey be conducted by a qualified biologist
within three days that any large stature trees are trimmed or felled to ensure that no
active nest is disturbed. It is presently unclear if any such action will occur as part of
this Project.
Hawaiian Hoary Bat
• Potential adverse impacts to Hawaiian hoary bat can be avoided or minimized by not
clearing woody vegetation taller than 4.6 m (15 ft) between June 1 and September
15, the bat pupping season.
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No-Action Alternative:
The No-Action Alternative involves no modifications to the existing LCC system is not
expected to impact flora or fauna.
4.7 Cultural, Historical, and Archaeological Resources
A 2016 survey of available information identified the presence of one historic site is in the vicinity
of the proposed wastewater collection system. Iin Pāhala, -- the Kaʻū High and Pāhala Elementary
School, is listed on the State of Hawai‘i register of historic places. No other historic sites are found
within the areas designated for improvements.
In November 2016, as part of the initial planning for LCC closure, a one-day archaeological field
inspection was conducted on the 42.5-acre parcel, which includes the 14.9-acre area for the
wastewater treatment and disposal facility. The inspection involved pedestrian sweeps of the
entire 42.5-acre parcel to determine the presence of historic properties or significant
archaeological features. The inspection report indicated that ground modifications carried out
during the plantation period had destroyed evidence of pre-contact agriculture or settlement
activities. The bulldozing associated with the creation of the macadamia nut orchard appeared to
have leveled any plantation-era land features.
The 2016 inspection identified one surface artifact as the only evidence of past human activity on
the 42.5-acre parcel. Th is surface artifacts included a single traditional artifact and numerous late
post-contact artifacts. The single traditional artifact, a crudely-shaped discoidal hammerstone,
was found on the ground surface near the northern edge of the plant site near Maile Street. No
other cultural material, either traditional or post-contact, was observed in this area, suggesting
that the hammerstone reflects an isolated artifact rather than a buried cultural deposit. Although
historical ground modifications have likely limited the archaeological potential of the site, the
discovery of both pre- and post-contact surface artifacts within the 42.5-acre plant parcel, as well
as evidence from plantation-era documents indicating the opening of a lava tube containing
human remains once existed in the southeastern corner of the parcel, suggests that further
archaeological studies may be necessary before any development can commence. The 2016
inventory report recommended at least an Archaeological Inventory Survey (AIS) to fully
document, map, date, and collect surface artifacts. It may also be necessary to test for the
presence of subsurface cultural deposits through hand excavation or mechanical trenching.
As part of previous Environmental Assessment efforts, the County conducted an AIS of the 14.9-
acre treatment and disposal facility, including subsurface testing of the effluent disposal area. To
carry out this AIS, SHPD approved an AIS plan. To meet this requirement, the County submitted
the AIS plan to SHPD on March 22, 2018. On April 25, 2018, SHPD requested clarification, and
responses, including findings from the 2016 field survey report and a map of the proposed
wastewater treatment and disposal facility, were submitted to SHPD on July 31, 2018. SHPD
approved the AIS plan on August 20, 2018, and the County conducted the AIS of the 14.9-acre
WWTP in September 2018.
In addition to the AIS, the County is obligated to comply with the National Historic Preservation
Act (NHPA). On March 29, 2018, the County initiated consultation for this project in accordance
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with Section 106 of the NHPA. Consultation letters were sent to various Native Hawaiian
Organizations, totaling 15 letters, inviting comments from organizations that may attach religious
or cultural significance to properties affected by the proposed actions. A letter dated February 20,
2020 from the SHPD provides concurrence that no historic properties at the Proposed WWTP Site
shall be affected, under HRS 63-8 and section 106
In 2023, an Archeological Literature Review was conducted to determine the likelihood that
historic properties may be affected by the project and, based on the findings, consider cultural
resource management recommendations. The literature review concluded that surface pre-
contact sites are not expected within the project area given the known traditional land use in this
area and the impacts of continued agricultural and residential development. The modern
development of the macadamia nut orchard has likely also obliterated any plantation era sites
once present in that part of the project area. Historic surface features associated with the sugar
plantation and associated village may be present. Furthermore, there is potential for pre- or post-
Contact subsurface archeological features within the project area, which may or may not be
located within lava tubes. It should be noted that the literature review is intended to support the
projects historic and environmental review process; however, the report does not fulfill the
requirements of an archeological inventory survey investigation as set forth in federal and State
Hawai’i historic preservation review requirements.
Impacts and Mitigation Measures:
All Proposed Alternatives:
Construction activities associated with the Proposed Action may potentially disturb
archaeological and cultural resources in the project area. An Archeological Inventory
Survey was conducted to assess potential impacts. Potential impacts may be avoided or
minimized further by performing subsurface testing to confirm the presence or absence
of resources on the wastewater treatment and disposal facility site. Archaeological
monitoring should also be implemented during IWS installation and maintenance.
If any archaeological sites or remains are encountered during construction, work shall
cease immediately, and SHPD shall be contacted to assess the significance of the find and
recommend appropriate mitigation measures, if necessary.
A letter dated February 20, 2020 from the SHPD provides concurrence that no historic
properties shall be affected, under HRS 63-8 and section 106 . It is advised that the County
seek to consult with SHPD in regard to Alternatives 3 and 4 in accordance with HRS
Chapter 6E requirements, and in relation to Section 106 of the National Historic
Preservation Act (NHPA) – if triggered – and, to incorporate additional impact avoidance
and minimization measures if required for the construction of the IWS.
No-Action Alternative:
The No-Action Alternative does not involve any new construction or disturbance of land,
and therefore, it does not result in impacts on archaeological and cultural resources.
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No specific mitigation measures related to archaeological and cultural resources are
required for this alternative.
These revised mitigation measures address the potential impact of archaeological and
cultural resources for all five alternatives, including the need for Archaeological Inventory
Surveys (AIS) and archaeological monitoring in Alternatives 3 and 4. Please let me know
if you need further adjustments or information.
4.8 Air Quality and Odors
The project area falls within the purview of ambient air quality standards (AAQS) at both national
(NAAQS) and state levels, encompassing the criteria pollutants, including carbon monoxide,
nitrogen dioxide, sulfur dioxide, lead, ozone, and particulate matter (PM10 and PM2.5). It is
noteworthy that the State of Hawaii has standards that align with national standards in terms of
stringency. The Hawaii Department of Health (DOH) operates an extensive network of air quality
monitoring stations across the state, ensuring that criteria pollutant levels have consistently
remained below both federal and state AAQS thresholds throughout the state, including the
Pāhala area.
Existing air quality within the Pāhala area is primarily influenced by various sources of air
pollutants, encompassing vehicular emissions, industrial activities, natural processes, and
agricultural practices. Additionally, the region is subject to periodic air quality fluctuations
resulting from volcanic emissions originating from Kīlauea Volcano. The concentration of volcanic
smog, locally known as "vog," within the area hinges on several factors, including the volume of
sulfur dioxide (SO2) emissions from Kīlauea, wind patterns, and prevailing atmospheric conditions.
It is pertinent to note that volcanic emissions are categorized as natural events, and in certain
circumstances, exceedances of the 1-hour NAAQS attributable to volcanic emissions might be
excluded from considerations regarding air quality attainment.
The Pāhala area, characterized by its rural nature, does not feature major stationary sources of
air pollution. Furthermore, the relatively low volume of vehicular traffic along Māmalahoa Highway
and within the community itself serves to limit the contribution of mobile sources of emissions to
air quality concerns.
Impacts and Mitigation Measures:
Alternatives 1 and 2 - Package Plant:
During the construction phase of the wastewater collection system and treatment facility
associated with Alternative 1, short-term impacts on air quality may manifest as fugitive
dust emissions resulting from construction activities. These emissions would be effectively
managed through the implementation of a comprehensive dust control plan. Measures
within this plan would encompass the application of water to active work areas, the use
of wind screens, vigilant maintenance of adjacent roads to prevent dust buildup, and the
covering of open-bodied trucks. It is plausible that exhaust emissions from mobile
construction equipment, in conjunction with traffic disruptions associated with
construction activities, could exert a minor influence on air quality during this phase.
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As previously discussed, the PER recommended a granular activated carbon (GAC)
scrubber be used at the Pahala WWTP headworks. A GAC scrubber passes odorous air
through a bed of activated carbon, which absorbs the odorous constituents within the
pore spaces of the carbon.
Chemical oxidation or reduction of some compounds can also occur. As pore spaces
become occupied, efficiency degrades, and the carbon must be replaced or regenerated.
Carbon is most effective on higher molecular weight molecules such as the organic sulfur
compounds, which makes it the technology of choice. Package GAC scrubbers are
available for small headworks and vessels can be situated vertically, horizontally or radially
to optimize footprints and reduce structure elevation profiles. The County currently
operates GAC scrubbers at other facilities and purchases the GAC media in bulk, which
reduces costs.
Once construction has been completed, emissions will occur from the daily visits to the
WWTP by a plant operator who could be based at the Hilo WWTP or at the Kealakehe
WWTP in Kona. Also, emissions would occur from trucks used to haul the solids to the
County West Hawai'i Sanitary Landfill at Puuanahulu, located north of Kailua Kona. These
trips are not expected to exceed federal or state ambient air quality standards for criteria
pollutants. The presence of an emergency standby diesel-powered generator, operated
periodically for testing and during power outages, is unlikely to have a significant adverse
impact on air quality.
Alternatives 3 and 4 - Individual Wastewater System Program:
Air quality impacts for Alternatives 3 and 4 primarily relate to the installation and
maintenance of the IWS by homeowners. These activities may yield minor emissions
associated with construction equipment and vehicles. However, any potential air quality
impacts would be transient and localized to specific residential areas. Additionally, there
is a slight ri sk of odors emanating from maintenance activities or system breakages within
the IWS. Homeowners would be responsible for managing and mitigating these potential
odors.
No-Action Alternative:
The No-Action Alternative entails no modifications to the existing LCC system and,
therefore, is not projected to introduce new air quality impacts to the Pāhala area.
Historical air quality records indicate that the area has consistently met ambient standards
during the operation of the existing LCCs.
4.9 Noise
The existing noise environment in the Pāhala area is primarily characterized by the natural sounds
of the rural surroundings, which include ambient sounds from vegetation, wildlife, and
intermittent vehicular traffic on Māmalahoa Highway and local streets. Noise levels in rural areas
like Pāhala are typically lower than in urban or industrial areas.
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Impacts and Mitigation Measures
Alternatives 1 and 2 - Package Plant:
During the construction of the wastewater treatment facilities and collection systems, it is
anticipated that there will be an increase in noise levels associated with the operation of
heavy machinery, construction equipment, and from potential increased vehicle traffic.
These construction activities can generate temporary noise impacts in the project area.
To minimize construction-related noise impacts, the project can implement standard noise
control measures such as scheduling construction activities during daytime hours, avoiding
noisy activities during quiet hours (e.g., evenings and weekends), and employing noise
barriers or sound-reducing equipment where feasible.
While construction may introduce short-term noise, the continuous operational noise from
these facilities is generally localized and can be controlled with noise-reducing measures.
Transportation noise may be minimal as wastewater can be treated onsite.
The operational phase of the wastewater treatment facilities may introduce continuous
noise sources, such as equipment operation, pumps, and mechanical systems. While these
noise sources are generally not excessively loud, they can contribute to ambient noise
levels in the immediate vicinity of the facilities.
To address operational noise, the project can consider noise-reducing designs for the
treatment facilities, such as noise barriers or acoustic enclosures for noisy equipment.
Additionally, maintenance schedules can be optimized to minimize noisy activities during
sensitive times.
Vehicle traffic associated travel to the Pāhala WWTP by plant operators and with trucks
needed to remove solids, based on the location of package plant would not affect noise
in the residential areas.
Alternatives 3 and 4 - Individual Wastewater System Program:
During construction of the IWS, it is anticipated that there will be an increase in noise
levels associated with the operation of heavy machinery, construction equipment, and due
to vehicle traffic. These construction activities can generate temporary noise impacts in
the project area.
To minimize construction-related noise impacts, the project can implement standard noise
control measures such as scheduling construction activities during daytime hours, avoiding
noisy activities during quiet hours (e.g., evenings and weekends), and employing noise
barriers or sound-reducing equipment where feasible.
The installation and maintenance of the IWS may result in localized noise during
construction and maintenance activities. However, these impacts are distributed across
multiple resident properties.
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No-Action Alternative:
This alternative maintains the existing LCC system. While it avoids construction-related
noise, it may not address long-term noise concerns associated with the aging
infrastructure.
4.10 Energy and Natural Resources
4.10.1 Energy Sources
The Pāhala area relies on a mix of energy sources for electricity, including fossil fuels (e.g., oil)
and renewable sources (e.g., solar and wind). The specific energy mix can vary over time and
may be influenced by state and county policies promoting renewable energy.
Although the integration of renewable energy sources to reduce reliance on fossil fuels and
promote sustainability can be considered, WWTP facilities typically rely on a consistent source
power. Also, the package plant site plan has been designed to minimize the affected land area.
Renewable energy sources would require a greater land area which would mean removal of
additional macadamia nut trees.
Impacts and Mitigation Measures
All Proposed Alternatives:
The construction and operation of wastewater treatment facilities will require energy
inputs. Construction equipment, pumps, aeration systems, and other mechanical
components consume energy during installation and operation.
Implementing energy-efficient technologies and practices during facility construction and
operation can help reduce energy consumption.
Additionally, the feasibility of incorporating renewable energy systems into the wastewater
treatment facilities to reduce carbon emissions and energy costs should be evaluated.
No-Action Alternative:
This alternative maintains the existing LCC system which may not address long-term
energy consumption associated with the aging infrastructure.
4.10.2 Land Use and Land Use Plans
The existing land use in the project area includes residential, agricultural, and undeveloped land.
Agricultural activities, such as macadamia nut farming, are important for the local economy. The
Project Area is located within the Urban and Agricultural State Land Use Districts. As such, the
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Proposed Action would be required to comply with the regulations set forth in the State Land Use
Law (HRS, Chapter 205).
Furthermore, the County of Hawai‘i General Plan calls for the preparation of community
development plans (CDPs) “to translate the broad General Plan statement to specific actions as
they apply to specific geographical areas.”
The Kaʻū CDP is one of nine CDPs for Hawai‘i County. On October 17, 2017, the Ka‘ū CDP was
adopted as Ordinance No. 2017-66. The purpose of CDPs is to implement the broad goals within
the General Plan on a regional basis and to translate the broad General Plan statements into
specific actions. CDPs are the forum for community input into managing growth and coordinating
the delivery of government services to the community. CDPs designate detailed development
patterns and direct physical development and public improvements by detailing land use policies
and infrastructure priorities.
Section 5 of the CDP prioritizes improvements in infrastructure, facilities, and services, including
Section 5.8 applicable to Environmental Management which states:
“Environmental management facilities, including expanded sewer lines, the Ocean View
transfer station, green waste facilities, and improvements in the Pāhala transfer station
Policy 120 Extend the primary wastewater collection lines in Pāhala and Nāʻālehu so that
infill development projects can connect wastewater systems built for new subdivisions to
the County systems.”
The collection system will be consistent with Policy 120 as the improvements for the Pāhala LCC
Replacement Project have been designed not to preclude expansion to accommodate the Pāhala
community. Similarly, the wastewater treatment and disposal facility has been designed not to
preclude expansion to accommodate the future needs of the Pāhala community. Future
subdivisions would be accommodated, as capacity allows, on a first-come, first-served basis.
Impacts and Mitigation Measures
Alternative 1 – Package Plant:
Construction activities will result in land disturbance, affecting natural habitats and
agricultural areas. Minimizing the affected area will act to footprint of construction
activities and implementing erosion control measures can help mitigate land disturbance
impacts. These centralized facilities may require significant energy inputs for treatment
and transportation of wastewater. However, they offer opportunities for energy efficiency
improvements and the integration of renewable energy sources.
The collection system has been designed allow flows from additional residential areas to
the north and east to reach the treatment and disposal facilities. The package plant site
plant has been designed to allow additional treatment capacity. Thus, Alternative 1 would
be consistent with the Ka‘ū CDP.
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Alternative 2
Although the package plant in Alternative 2 would allow additional facilities, u se of existing
collection system would not allow flows from the residential areas to the north and east
to connect to the package plant and treatment disposal system.
Alternatives 3 and 4 – Individual Wastewater System Program:
Construction activities can result in land disturbance, affecting natural habitats and will
affect the residential parcels, including affecting existing buildings, structures and
landscaping. Minimizing the footprint of construction activities and implementing erosion
control measures can help mitigate land disturbance impacts.
These alternatives are designed to use gravity flows which will mean lower energy
demands compared to centralized facilities.
No-Action Alternative:
The existing LCC system will not require energy consumption. No significant changes in
energy use are anticipated with this alternative.
4.11 Roadways and Traffic
The existing roadway and traffic conditions in the Pāhala area provide essential context for
assessing the impacts and mitigation measures associated with the proposed wastewater
treatment project. Key considerations include:
Road Network: Pāhala is served by a network of roadways which are under the jurisdiction of the
County and include Māmalahoa Highway, a state facility. The local streets provide access to
residences, businesses, and community facilities.
Traffic Volume: The traffic volume on Māmalahoa Highway and local roads in Pāhala is generally
low, reflecting the rural nature of the area. Limited vehicular traffic contributes to low levels of
congestion and a relatively peaceful road environment.
Access to Project Sites: The proposed project sites, including the preferred location for the
wastewater treatment and disposal facility, are accessible via the existing road network.
Consideration of the impact of construction and operational traffic on local roads is necessary.
Safety: Road safety is a critical concern in the area. Ensuring the safety of residents, commuters,
and workers during construction and operation is a primary focus. Safety measures may include
signage, flaggers, and traffic control measures as needed.
Impacts and Mitigation Measures:
Alternatives 1 and 2 – Package Plant:
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During the construction phase of the wastewater treatment project, temporary disruptions
to traffic flow on local roads may occur. Mitigation measures include the development of
traffic management plans to minimize construction-related traffic impacts. These plans
may include designated construction access points, scheduling work during off-peak
hours, and flaggers to ensure safe traffic flow.
The influx of construction vehicles, equipment, and workers to the project sites may result
in increased traffic volume on local roads. To mitigate this, construction logistics planning
should aim to minimize the impact on existing road users and ensure the safety of all road
users.
Safety measures, such as signage, temporary speed limits, and traffic control personnel,
will be employed as necessary during construction activities to maintain the safety of both
workers and the local community.
As part of the project, any necessary upgrades or improvements to local roads or
intersections impacted by construction activities will be considered and implemented. This
may include road repairs, resurfacing, or other enhancements to ensure the continued
integrity of roadways.
During the operation of the wastewater treatment facility, regular visits by facility
operators are expected. While these visits would introduce minimal traffic, safety remains
a priority, and any potential traffic impacts will be mitigated through adherence to
established safety protocols.
Continuous monitoring of traffic conditions and adherence to traffic management plans
will be essential to address any unforeseen issues promptly. Compliance with local traffic
regulations and safety standards will be enforced throughout the project's lifecycle.
In summary, the existing road network in Pāhala serves as the backdrop for assessing
potential impacts and mitigation measures associated with the proposed wastewater
treatment project. During both the construction and operation phases, careful planning,
safety measures, and infrastructure improvements will be implemented to minimize
disruptions and maintain the safety and functionality of local roadways.
Additionally, the new collection system or methods of integration with the existing
collection system may require careful planning and engineering to ensure compatibility
and minimize impacts on the existing infrastructure.
Alternatives 3 and 4 - Individual Wastewater System Program:
Unlike the centralized package plant options, this alternative involves the installation and
maintenance of the IWS at each residence within the service area. Logistically, this can
be challenging due to the need for coordination with numerous property owners.
Obtaining access to private properties and ensuring compliance with installation and
maintenance requirements for IWS may pose logistical hurdles. Coordinating schedules
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and ensuring proper installation and maintenance become complex tasks; however, it
should be noted that septage trucks would only need to visit each property every three to
five years to pump the septic tanks.
The ongoing operation and management of multiple individual systems can be logistically
complex. Ensuring that all systems meet required standards and addressing any issues
promptly is a continuous endeavor.
No-Action Alternative:
Maintenance of Existing Infrastructure: Under the No-Action Alternative, there would be
no changes to the existing infrastructure. While this avoids the logistical challenges of new
construction, it doesn't address potential issues with the aging LCC system.
Long-Term Considerations: Continuing with the existing system may provide short-term
stability, but it may not be a sustainable long-term solution for wastewater treatment in
the area.
4.12 Hazardous Materials
The existing conditions in Pāhala regarding hazardous materials primarily pertain to the operation
of the Pāhala LCCs, which historically managed wastewater treatment for the community. No
chemicals are currently being used for treatment at the Pāhala LCCs, however, wastewater
treatment processes generate residual waste, including sludge and biosolids. Proper management
and disposal of these materials are essential to prevent environmental contamination.
Impacts and Mitigation Measures:
All Proposed Alternatives
The impacts and mitigation measures related to hazardous materials are primarily
associated with the closure of the Pāhala LCCs and the transition to alternative wastewater
treatment methods:
• As the LCCs cease operation, residual waste, such as sludge and biosolids, must
be managed appropriately. Mitigation involves planning for the safe removal and
disposal of these materials to prevent adverse environmental impacts.
• Depending on the condition of the LCC sites, remediation efforts may be required
to address any soil or groundwater contamination resulting from historical
operations. Remediation plans and measures will ensure that the sites are restored
to acceptable environmental standards.
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• For proposed alternative wastewater treatment methods, any hazardous materials
or chemicals used in the new treatment processes would be subject to stringent
safety protocols, handling procedures, and storage requirements. Mitigation
measures include compliance with safety regulations and ongoing staff training.
Continuous monitoring of the environment by the homeowners, including soil and water
quality, will be essential to detect any potential impacts related to hazardous materials.
Mitigation measures involve the implementation of robust monitoring programs to
promptly address any issues that may arise.
The closure of the Pāhala LCCs and the transition to alternative wastewater treatment
methods in Pāhala require careful management of hazardous materials and chemicals to
prevent adverse environmental impacts. Proper disposal, remediation, and adherence to
safety protocols are crucial mitigation measures to ensure the safe and responsible
handling of hazardous materials throughout the project's lifecycle.
No-Action Alternative:
The No-Action Alternative does not involve any new construction or modification of the
existing sewage system; however, this would not allow the County to meet the
requirements of the AOC and SDWA.
4.13 Socioeconomics & Environmental Justice
In December 2022, the State of Hawaiʻi Department of Business, Economic Development and
Tourism released 2021 population estimates for the state and counties. This analysis estimates
that Hawaiʻi County had a resident population of 200,648 persons in 2021, which represents an
annual increase of 1.01 percent from the 2016 population.
The U.S. Census Bureau provides the American Community Survey (ACS) for Census Designated
Places, which updates selected demographic, social, and economic information for various years.
The ACS shows age distribution, racial composition, and economic information, including
employment and household income by Census Designated Place for various locations in Hawaiʻi
County. The version of the ACS referenced is the 2021 5-Year Estimates, released in December
2022. See Table 4.1 below.
The ACS shows the Pāhala population has a much younger age distribution compared to Hawai‘i
County, especially in the proportion of individuals in the “Under 5 to 19” age category, 33.0
percent compared to 23.6 percent for the County. This proportion applies to all age groups,
except for the 35 to 59 and the 60 to 74 age groups. The median age for Pāhala is 27.0 years
compared to 43.0 years for the County.
Overall, Pāhala is characterized by a racial composition that includes a greater proportion of
minorities compared to the County. The Pāhala racial distribution includes a much lower
proportion of White residents, a much higher proportion of Filipino residents, and lower
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populations of other minority groups, including Native Hawaiians when compared to the County.
There are also more residents of two or more races in Pāhala than in the County.
Table 4.1
Demographic, Economic and Social Characteristics of Pāhala and Hawai'i County
Item
Pāhala Hawai'i County
Total Percent Total Percent
Demographic Characteristics
Total Population 2,210 200,468
Under 5 to 19 years 730 33.0 47,349 23.6
20 to 34 years 602 27.2 33,056 16.5
35 to 59 years 493 22.3 61,169 30.5
60 to 74 years 285 12.9 43,854 21.9
75 years and older 100 4.5 15,040 7.9
Median age 27 43
Race
White 388 17.6 65,306 32.6
African American (inc American Indian/Alaska Native) 0 0.0 2,608 1.3
Chinese 0 0.0 2,911 1.5
Filipino 555 25.1 19,111 9.5
Japanese 46 2.1 16,179 8.1
Korean 0 0.0 888 0.4
Other Asian 60 2.7 5,172 2.6
Native Hawaiian 65 2.9 18,333 9.1
Other Pacific Islander 33 1.5 5,765 2.9
Some other race 0 0.0 4,586 2.3
2 or more races 1,063 48.1 59,754 29.8
Social/Educational Characteristics
Less than 9th grade 78 6.2 3,289 2.3
High School to High School Graduate 526 42.1 49,116 34.3
Some college to associate degrees 386 30.9 47,704 33.3
Bachelor degree 227 18.2 27,845 19.4
Graduate/professional degree 32 2.6 15,395 10.7
Household Income Characteristics
Less than $24,999 129 25.0 13,462 18.9
$25,000 to $49,999 106 20.5 13,039 18.3
$50,000 to $99,999 156 30.2 21,696 30.4
$100,000 to $199,999 91 17.6 17,775 24.9
$200,000 or more 35 6.8 5,430 7.6
Median household income $54,293 $68,399
Employment Characteristics
Agriculture, forestry, fishing and mining 268 32.4 4,357 4.9
Construction 14 1.7 7,051 7.9
Manufacturing and wholesale trade 188 22.7 3,920 4.4
Retail trade 37 4.5 10,881 12.2
Transportation, warehousing, and utilities 19 2.3 3,679 4.1
Information tech, finance, insurance and real estate 31 3.7 6,140 6.9
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Table 4.1
Demographic, Economic and Social Characteristics of Pāhala and Hawai'i County
Professional, scientific and technical services 41 5.0 10,366 11.6
Education and health care 117 14.1 19,354 21.7
Arts, entertainment and recreation 100 12.1 14,078 15.8
Other services, public administration 12 1.5 9,493 10.6
Pāhala has a higher proportion of residents that have completed high school and some college
than the County overall, but a slightly lower proportion with college degrees (bachelor’s and
graduate or professional degrees). From an economic perspective, Pāhala generally has more
households in lower income brackets than the County, and a lower median household income.
Lastly, Pāhala had a higher proportion of employment in agriculture, forestry, fishing, hunting,
and construction (32.4 percent), and in manufacturing and wholesale trade (22.7 percent)
compared to the County 4.9 percent) and 4.4 percent respectively. Pāhala had a lower proportion
in education and health care (14.1 percent), compared to the County (21.7 percent).
A subset of social resources is environmental justice. Environmental justice considers sensitive
populations, such as children, minorities, and low-income communities. Sensitive populations are
identified in two Executive Orders (EOs):
• EO 12898, Federal Actions to Address Environmental Justice in Minority and Low-Income
Populations, serves to avoid the disproportionate placement of adverse environmental,
economic, social, or health impacts from federal actions and policies on minority and
low-income populations.
• EO 13045, Protection of Children from Environmental Health Risks and Safety Risks,
states that federal agencies will identify and address environmental health and safety
risks from their activities, policies, or programs that may disproportionately affect
children.
As noted above and in Table 4.1, Pāhala has a higher proportion of low-income, minority, and
children residents as compared to the County as a whole. For purposes of this assessment, and
to correspond with the available ACS demographic characteristic data, “low income” is defined as
having a household income of less than $24,999; “minority” is defined as any race population
other than White; and “children” is defined as the “Under 5 to 19” age category.
Alternatives 1 and 2 - Package Plant:
In the short term, construction projects would require a number of contractors and their
subcontractors. Construction contract documents would reference HRS 103B, which
requires the contractor (including subcontractors) to include not less than 80 percent
Hawai‘i residents in the work force. This would limit the importation of workers from
outside the local area and the associated increase in demand for local housing.
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The Alternative 1 would generate employment as the contractor would need workers to
undertake construction of the improvements for the wastewater collection system and the
WWTP and effluent disposal facility. This employment would generate wages and salaries
paid to the contractor and subcontractor work forces. The wages and salaries paid to the
work force would in turn generate purchases of goods and services, which would result in
taxes paid to the State of Hawai‘i. In addition, the contractor and their subcontractors
would need to purchase equipment, supplies, and materials, some of which would be
purchased from local suppliers and vendors. Direct purchases of equipment, supplies, and
materials by the contractor would also generate taxes. Overall, Alternative 1 would result
in positive employment benefits which would result in higher levels of income and overall
economic benefits to the local economy.
The Alternative 1 is not likely to directly impact long-term employment or education trends
since the wastewater plant operator would likely be based in Hilo or Kona, meaning the
project would not involve long-term relocation of any staff to Pāhala. Additionally,
Alternative 1 wastewater collection system and treatment and disposal facility would not
be designed to encourage or accommodate substantial population growth in Pāhala.
Alternatives 3 and 4 - Individual Wastewater System Program:
Construction of the IWS would also create the need for workers construct the septic
system including the absorption bed or seepage pits. Since the IWS would not involve the
complex treatment processes, the level of employment could be lower than Alternative 1
or 2. However, to construct over 100 IWS would require multiple crews or contactors.
Overall, the economic impact may be similar to Alternatives 1 and 2.
No-Action Alternative:
The No-Action Alternative does not involve any new construction or modification of the
existing sewage system, and therefore, it is not expected to impact socioeconomic or
demographic conditions in the Pāhala area.
No specific mitigation measures related to socioeconomic characteristics are required for
this alternative.
These adapted impacts and mitigation measures address the potential socioeconomic
impacts for all five alternatives, emphasizing employment and economic benefits while
considering sensitive populations. Please let me know if you need further adjustments or
information.
All Proposed Alternatives:
Despite the relatively high proportions of low-income, minority, and children residents in
Pāhala compared to the County overall, the proposed alternatives would not result in
disproportionately high and adverse human health or environmental effects on the
minority or low income populations. The design and location of the proposed wastewater
treatment and disposal facility would minimize odor and air quality impacts. Construction
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of the wastewater collection system would result in intermittent and unavoidable noise
from construction vehicles and equipment within the Pāhala community, including noise
associated with the removal of bedrock. However, as discussed in Section 3.18.2,
construction activities within the community would comply with provisions of HAR 11-46
(Community Noise Control). This includes obtaining a noise permit for any activities that
would generate noise exceeding the permissible sound levels specified in HAR 11-46. The
permit would limit excessive noise sources to daytime hours; would require the use of
best available control technology to control noise levels from excessive noise sources; and
would require the applicant to notify affected members of the public in advance of any
planned nighttime construction activity (which must not exceed the permissible sound
levels). Overall, the proposed alternatives are expected to result in positive human health
and environmental effects to Pāhala residents by providing a cleaner and longer-lasting
wastewater treatment system.
Concerns regarding the financial impact of the project on individual newly accessible
property owners (due to the requirement to connect to the new wastewater collection
system, per HCC § 21-5) were raised by the community during the December 2017 public
meetings and also echoed at the the October 2018 public meeting for the previous Draft
EA. Although not required by HAR 11-200, the County voluntarily convened an additional
public meeting on March 21, 2019 to gain further input from newly accessible property
owners and fulfill a County commitment made in October 2018 to research and provide
financing options available to owners of parcels that would become newly accessible to
the County collection system. Available programs discussed included:
• U.S. Department of Housing and Urban Development (HUD) with County of
Hawaiʻi Office of Housing and Community Development Residential Repair
Program – Community Block Grant Program, and
• U.S. Department of Agriculture – Rural Development (USDA-RD) Program.
As noted during the March 2019 presentation, these programs may change in the coming
years and additional options may be added to this preliminary list. Hawaiʻi Legislature,
Senate Bill 221 SD1, which could amend HRS 342D to establish a low-interest loan
program offering financial assistance to cesspool owners to connect to wastewater
treatment systems approved by the DOH, was also discussed; however, this bill was
subsequently not passed during the 2019 legislative session.
Abandonment of the two LCCs, and abandonment of the existing wastewater collection
system would have no impact on socioeconomic resources within Pāhala.
4.14 Sustainability
The concept of sustainability is vital in understanding the environmental, economic, and social
conditions in Pāhala and its surrounding areas. Sustainability encompasses the balance between
meeting the needs of the present without compromising the ability of future generations to meet
their own needs. In the context of Pāhala, several factors influence the existing conditions related
to sustainability:
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Pāhala's environmental sustainability is influenced by its unique natural surroundings, including
its proximity to the Kīlauea Volcano and the potential impact of volcanic activity on air and water
quality. The region's lush vegetation and agricultural activities contribute to its environmental
diversity.
The local economy in Pāhala is characterized by agriculture, including macadamia nut farming,
which has been a significant contributor to the region's economic sustainability. Additionally,
employment opportunities in education and healthcare play a role in the local economy.
Pāhala's community is diverse, with residents from various racial backgrounds, including a
significant Filipino population. The region's social sustainability is influenced by factors such as
education levels, access to healthcare services, and community engagement.
Impacts and Mitigation Measures:
Alternatives 1 and 2 - Package Plant:
The construction of a new wastewater collection system and treatment facility may have
short-term environmental impacts, such as soil disturbance and potential disruption of
local ecosystems. Mitigation measures include adherence to environmental regulations
and best construction practices to minimize ecological disturbances.
The construction phase is expected to generate employment opportunities, contributing
positively to economic sustainability in the short term. Long-term economic impacts
include the potential for increased economic activity due to improved wastewater
infrastructure.
Minimal direct social impacts are expected during construction. The long-term social
benefits include improved access to wastewater services, contributing to the overall
quality of life and social sustainability.
Alternative 3: Individual Wastewater System-Maintenance Contract Model
The installation and maintenance of the IWS may have minimal environmental impacts,
mainly related to construction activities. Mitigation measures involve adherence to
environmental regulations during installation.
This alternative provides opportunities for local residents to participate in the installation
and maintenance of IWS, potentially benefiting economic sustainability at the community
level.
The social impacts are localized, involving homeowners and their immediate surroundings.
The long-term social benefit includes improved wastewater systems for individual
households, enhancing overall social sustainability.
Alternative 4 - Individual Wastewater System-Operating Permit to Homeowners:
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Similar to Alternative 3, this alternative's environmental impacts are mainly related to the
installation and operation of the IWS. Mitigation measures include compliance with
environmental regulations.
The economic impacts are similar to Alternative 3, with opportunities for local participation
in IWS installation and maintenance, supporting economic sustainability at the community
level.
The social impacts are localized, involving homeowners and their immediate communities.
The long-term social benefit includes improved wastewater systems for individual
households, enhancing social sustainability.
No-Action Alternative:
This alternative maintains the existing conditions, resulting in minimal changes to the
environment.
The economic impacts of the No-Action Alternative are limited, as it does not involve new
construction or economic development related to wastewater infrastructure.
This alternative does not introduce significant social changes, as it maintains the status
quo in terms of wastewater services and community conditions.
Overall, each alternative has varying short-term and long-term impacts on environmental,
economic, and social sustainability in Pāhala. Mitigation measures and adherence to
regulations are essential to minimize adverse effects and enhance the region's overall
sustainability.
4.15 Human Health And Safety
In Pāhala, as in any community, access to adequate wastewater treatment services is a
fundamental necessity for maintaining public health and environmental quality. Existing
conditions reveal the following:
• Proper wastewater treatment is vital for safeguarding public health. Inadequate treatment
can result in the contamination of groundwater and surface water, posing risks to drinking
water sources and recreational areas. It can also lead to the spread of waterborne
diseases.
• Effective wastewater treatment is essential for preserving the local environment.
Uncontrolled discharge of untreated sewage can harm aquatic ecosystems, damage coral
reefs, and degrade coastal waters, impacting the region's biodiversity and natural beauty.
• Reliable wastewater treatment infrastructure contributes to the overall well-being of the
community. It ensures that residents can enjoy a safe and healthy environment and
minimizes nuisances such as foul odors and unsightly conditions associated with
inadequate treatment.
The Closure of the LCCs and Improved Services
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The closure of the LCCs and the proposed wastewater treatment alternatives aim to address
existing challenges and improve wastewater treatment services in Pāhala:
• The closure of the LCCs signifies a shift towards more modern and effective wastewater
treatment methods. The proposed alternatives include advanced treatment processes that
can remove a higher percentage of contaminants from wastewater, resulting in cleaner
effluent.
• Improved wastewater treatment aligns with the community's commitment to
environmental stewardship. By ensuring that treated effluent meets stringent quality
standards, the closure of the LCCs supports the conservation of local ecosystems and
marine life.
• The closure of the LCCs and the adoption of alternative wastewater treatment methods
provide significant public health benefits. Treated wastewater reduces the risk of
waterborne diseases and protects the health of residents and visitors.
• Adequate wastewater treatment services contribute to community satisfaction and quality
of life. Residents can enjoy a cleaner and healthier environment, which, in turn, can have
positive social and economic impacts on the community.
The closure of the LCCs represents a critical step toward enhancing wastewater treatment
services in Pāhala. It reflects the community's commitment to protecting public health,
conserving the environment, and improving overall community well-being. The proposed
alternatives offer modern and effective solutions to ensure that wastewater is treated to the
highest standards, addressing the pressing need for adequate wastewater treatment in the
area.
Impacts and Mitigation Measure
All Proposed Alternatives
The Pāhala LCC Closure project would not result in construction of new above-ground
infrastructure within the 500-year floodplain. Although a small portion of the proposed
collection system is located within the 500-year floodplain, the associated trenching
operations would be temporary and would not alter the 500-year floodplain. Thus, no
impacts to the existing floodplain are expected from the Proposed Action. For
information related to stormwater management and impacts, please refer to Section
3.23.
Abandonment of the two LCCs and the existing wastewater collection system would not
affect floodplains within the affected areas.
No-Action Alternative
The No-Action Alternative, specifically the continued operation of LCC 1, could lead to
impacts during a flooding event. LCC 1 is located very close to an area mapped as within
the 0.2-percent annual chance (500-year) floodplain. The existing collection system is
substandard and in poor condition. A large flood could potentially cause the collection
system and/or LCC to overflow as a result of stormwater inflow and result in an
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uncontrolled release of raw sewage, thus potentially contaminating flooded areas and
creating a public health hazard.
4.16 Unresolved Issues
This EID serves to assess the anticipated environmental impacts of each alternative on various
environmental resources; however, there are still several unresolved issues that may affect the
completion of the project under any of the Proposed Alternatives.
Construction Feasibility
Many of the lots in Pahala may be too small to construct individual septic systems, and for those
that could accommodate a septic tank, the soils may have percolation rates that are too slow to
allow for seepage pits based on HAR 11-62-34 regulations. Residents with insufficient space for
a seepage pit may need to import fill soil to create elevated mound systems or convert to
household aerobic treatment units.
Additionally, as discussed throughout the EID, the IWS recommended by the PER also requires
the installation of a septic tank with an absorption bed. The PER further outlines that this
absorption shall not be installed on lands with a slope gradient of greater than 8 percent. In light
of this, some lots may be better served by an IWS featuring a seepage pit which may only be
permitted when it can be demonstrated that an alternative means of disposal was not possible.
Access to Properties
Under Alternative 3, the County will fund, design, and manage project. Obtaining Right of Entry
(ROE) to private properties for various purposes, such as infrastructure development or land
surveys, can present several challenging issues. The process often involves negotiation, legal
considerations, and respect for property rights. Failing to clarify these issues can lead to legal
disputes and project delays. The most straightforward way to gain ROE is through the voluntary
consent and permission of property owners. However, some property owners may be unwilling to
grant access due to concerns about privacy, property damage, or other reasons.
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5. References
Atlas of Hawaiian Watersheds & Their Aquatic Resources, Island of Hawaii, Bishop Museum &
Division of Aquatic Resources. 1262 p. (3 volumes). Parham, J.E., G. R. Higashi, E. K.
Lapp, D.G. K. Kuamo‘o, R. T. Nishimoto, S. Hau, J. M. Fitzsimons, D. A. Polhemus, and W.
S. Devick. 2008.
County of Hawai‘i, Planning Department. County of Hawai‘i General Plan. Ordinance No. 05-025.
February 2005.
County of Hawai‘i, Planning Department. Ka‘ū Community Development Plan, Draft for Public
Review. March 2015.
County of Hawai‘i, Planning Department. 2017 Ka‘ū Community Development Plan, Ordinance
2017-66. October 2017.
County of Hawai‘i, Department of Environmental Management. Final Environmental Assessment
– Finding of No Significant Impact, the Nā‘ālehu-Pāhala Large Capacity Cesspool
Conversion. August 2007.
US Environmental Protection Agency and County of Hawai‘i, Department of Environmental
Management. Final Environmental Assessment for the Pāhala Large Capacity Cesspool
(LCC) Replacement Project, EPA Grant XP-96942401. February 2020.
County of Hawai‘i, Department of Environmental Management. Pāhala Large Capacity Cesspool
Closure Project, Revised Preliminary Engineering Report. April 2023.
County of Hawai‘i, Department of Public Works. Final Environmental Assessment and – Finding
of No Significant Impact, Ka‘ū Gym and Shelter, Pāhala, Ka‘ū District. April 2012.
Executive Order No. 11990, 42 FR 26961, 3 CFR, p. 121, 1977, as amended by Executive Order
No. 12608, 52 FR 2923, 1987.
Executive Order No. 11988, 42 FR 26951, 3 CFR, p. 117, 1977, as amended by Executive Order
Nos. 12148, 44 FR 43239, 3 CFR, p. 412, 1979 and 13690, 81 FR 57401, 44 CFR 9, p.
57401, 2016.
Executive Order No. 12898, 59 FR 7629. 1994.
Hawai‘i County Code 1983 (2016 Edition, as amended). Chapter 21. Sewers Hawai‘i County Code
1983 (2016 Edition, as amended). Chapter 25. Zoning Hawai‘i Revised Statutes, Chapter
205, Land Use Commission. 2017.
National Oceanic and Atmospheric Administration (NOAA). 2002. Department of Commerce,
National Oceanic and Atmospheric Administration. 50 CFR 600. Magnuson-Stevens Act
Provisions; Essential Fish Habitat (EFH). Federal Register Volume 67, Number 12
(Thursday, January 17, 2002) 2343-2483.
National Oceanic and Atmospheric Administration – National Marine Fisheries Service (NOAA-
NMFS). 2007. Magnuson-Stevens Fishery Conservation and Management Act, Public Law
94- 265, as amended by the Magnuson-Stevens Fishery Conservation and Management
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Reauthorization Act (P.L. 109-479), an act to provide for the conservation and
management of the fisheries, and for other purposes. 16 U.S.C. § 1801-1884.
State of Hawai‘i. Department of Agriculture. 2012 Census of Agriculture – County Data 2012.
State of Hawai‘i. Department of Health. Annual Summary 2015 Air Quality Data. December 2016.
State of Hawai‘i. Department of Health. Noise Reference Manual – Big Island Edition. Revised July
2017.
State of Hawai‘i. Hawai‘i Administrative Rules, Title 11 (Department of Health), Chapter 23
(Underground Injection Control). October 11, 2011.
State of Hawai‘i. Hawai‘i Administrative Rules, Title 11 (Department of Health), Chapter 46
(Community Noise Control). September 1996.
State of Hawai‘i. Hawai‘i Administrative Rules, Title 11 (Department of Health), Chapter 54 (Water
Quality Standards). Revised November 15, 2014.
State of Hawai‘i. Hawai‘i Administrative Rules, Title 11 (Department of Health), Chapter 62
(Wastewater Systems). March 21, 2016.
University of Hawai‘i at Hilo, Department of Geography. 1998. Atlas of Hawaii. Third Edition.
U.S. Census Bureau, 2012-2016 American Community Survey. U.S. Census Bureau’s American
Community Survey Office, 2017. Web. August 1, 2018.
U.S. Department of Agriculture Soil Conservation Service. Ka‘ū River Basin Study, County of
Hawai‘i. February 1994.
U.S. Environmental Protection Agency (EPA). Process Design Manual: Land Treatment of
Municipal Wastewater Effluents. EPA/625/R-06/016. Office of Research and Development.
Cincinnati, Ohio. September 2006.
U.S. Environmental Protection Agency (EPA). Climate Resilience Evaluation and Awareness Tool
(CREAT) Climate Scenarios Projection Map. Web. Accessed February 6, 2020.
US Environmental Protection Agency:
7 U.S.C. § 4201. 1981.
16 U.S.C. §§ 1271-1287. 1968.
16 U.S.C. §§ 1361 et seq. 1972.
16 U.S.C. §§ 1451-1464. 1972.
16 U.S.C. § 1531. 1973.
16 U.S.C. § 1801. 1976.
16 U.S.C. § 3501. 1982.
16 U.S.C. § 661. 1934.
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16 U.S.C. § 668-668c. 1940. 16
U.S.C. § 703 et seq. 1918.
33 U.S.C. § 403. 1899.
33 U.S.C. § 1251 et seq. 1948.
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42 U.S.C. § 7401 et seq. 1970.
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54 U.S.C. § 312502. 1974.
Environmental Information Document
Pahala Large Cesspool Closure