Consumer Confidence Report (CCR)
2023 Water Quality Report
Okuma Recreational Area
Okinawa, Japan
Introduction
This is an annual report on the quality of tap water delivered to Okuma
Recreational Area, Okinawa, Japan. The purpose of this report is to provide
you, our customers, with general information about the quality of water you
drink. In order to ensure that tap water is safe to drink, the Environmental
Protection Agency (EPA) prescribes regulations that limit the amount ofcertain contaminants in water provided by public water systems. Food andDrug Administration (FDA) regulations establish limits for contaminants inbottled water, which must provide the same protection for public health. In
Japan, the Government of Japan (GOJ) and the United States Forces Japan,
also regulate the quality of drinking water through the Japanese Environmental
Governing Standards (JEGS) which apply the EPA standards to our water
system.
What is a Consumer Confidence Report?
In 1996, Congress amended the Safe Drinking Water Act to require that allcommunity water systems in the United States deliver to their customers abrief annual water quality report called a Consumer Confidence Report (CCR).
Is my water safe?
Our water is safe to drink. No one is interested more in the high quality of ourdrinking water than the 18th Operational Medical Readiness Squadron,
Bioenvironmental Engineering Flight. We are committed to providing safe
drinking water to you at all times. Our routine monitoring program, which
follows water quality standards and monitoring requirements set forth in the
JEGS, enables us to maintain optimal water quality on Okuma Recreational
Area.
Do I need to take special precautions?
Although our water is safe to drink and meets all water quality standards, somepeople are more susceptible to contaminants in drinking water than the general
population. Immuno-compromised persons such as persons with cancer andundergoing chemotherapy, persons who have undergone organ transplants,
people with HIV/AIDS or other immune system disorders, some elderly, andinfants can be particularly at risk. These people should seek advice about
drinking water from their health care providers. EPA/CDC guidelines onappropriate means to lessen the risk of infection by Cryptosporidium and othermicrobial contaminants are available from the Safe Drinking Water Hotline(800–426–4791).
Are contaminants in my drinking water?
Drinking water, including bottled water, may reasonably be expected tocontain at least small amounts of some contaminants. The presence ofcontaminants does not necessarily indicate that water poses a health risk. Moreinformation about contaminants and potential health effects can be obtained bycalling the EPA’s Safe Drinking Water Hotline (1-800-426-4791). As water
travels over the surface of the land or through the ground, it dissolves naturally
occurring minerals and, in some cases, naturally-occurring radioactive
material, and can pick up substances resulting from the presence of animals orfrom human activity.
Microbial contaminants, such as viruses and bacteria, may come from sewage
treatment plants, septic systems, agricultural livestock operations, andwildlife. Inorganic contaminants, such as salts and metals, can be naturallyoccurring or result from urban stormwater runoff, industrial or domestic
wastewater discharges, oil and gas production, mining, or farming. Pesticides
and herbicides may come from a variety of sources such as agriculture, urban
stormwater runoff, and residential uses. Organic chemical contaminants,
including synthetic and volatile organic chemicals, are by-products ofindustrial processes, petroleum production, and can also come from gas
stations, urban stormwater runoff, and septic systems.
Radioactive
contaminants can be naturally occurring or be the result of oil and gas
production and mining activities.
Okuma Water System Information
The Okuma Recreational Area drinking water system and treatment plant is
operated and maintained by the 18th Force Support Squadron, Detachment 1.
The water is pumped into the installation water treatment plant from the HijiRiver then gravity-fed into the distribution system.
Monitoring of your drinking water
The 18th Operational Medical Readiness Squadron, Bioenvironmental
Engineering Flight is responsible for drinking water monitoring of Air Forceowned or managed installations, including military family housing on
Okinawa. We are committed to providing safe drinking water to you at all
times. We use only EPA and GOJ approved laboratory methods to analyze
your drinking water.
Trained personnel collect water samples from the
distribution system and resident’s taps. Samples are then shipped to an
accredited laboratory where a full spectrum of water quality analyses isperformed.
We at the Bioenvironmental Engineering Flight along with the Water and Fuels
System Maintenance Flight are proud of the opportunity to provide you withclean drinking water. We work around the clock to provide top quality drinking
water to every tap. We ask that all our customers continue to help us protect
and conserve our water sources and contact us if you have concerns about thesafety or dependability of your drinking water.

For More Information Contact:
18th Operational Medical Readiness Squadron,
Bioenvironmental Engineering Flight
DSN: 634-4752
Commercial: 098-938-1111 ext. 634-4752
基地内：634-4752

18th Civil Engineer Squadron,
Customer Service
DSN: 634-2424
Commercial: 098-938-1111 ext. 634-2424
基地内：634-2424

基地外から：098-938-1111 ext. 634-4752

基地外から：098-938-1111 ext. 634-2424

2023 Water Quality Table
TABLE 1: REGULATED CONTAMINANTS4
This table summarizes the monitoring results for all detected regulated contaminantsViolation?
Yes/NoUnits

Highest Level Detected

Limit(MCL or MRDL)

Goal(MCLG or
MRDLG)

Nitrate

No

ppm

0.11

10

10

Nitrite + Nitrate

No

ppm

0.11

10

10

Violation?
Yes/NoUnits

90th
Percentile
Results

Number of
Sites
ExceedingAL

Action Level3

Goal(MCLG)

Lead3

No

ppb

1.5

0

15

0

Copper3

No

ppm

0.015

0

1.3

1.3

Violation?
Yes/NoUnits

Highest Level Detected

No

N/A

0 positive samples

Goal(MCLG)
0 positive
samples

Turbidity

YES
TABLE 4NTU

Disinfectant

Violation?
Yes/NoUnits

Results

Limit(MCL or MRDL)≥ 2 positive
samples/month1
percentage ofsamples<0.3
Limit(MCL or MRDL)

No

ppm

0.64 (0.24 – 1.4)

4

4

Disinfection byproduct

Violation?
Yes/NoUnits

Results

Limit(MCL or MRDL)

Goal(MCLG)

Total Trihalomethanes(TTHMs)2

No

ppb

51.8 (2.2 – 51.8)

80

N/A

Halo-Acetic Acids (HAA5)2

No

ppb

1.4 (N.D – 1.4)

60

N/A

Inorganic Contaminants

Inorganic Contaminants

Microorganisms1
Total Coliform Bacteria

Chlorine0
all samples below 0.3

0Goal(MCLG)

Typical Source of Contamination

Runoff from fertilizer use; leaching septic
tanks/sewage; erosion of natural deposits

Typical Source of Contamination

Corrosion from household plumbing systems,
erosion of natural deposits
Typical Source of Contamination
Naturally present in the environment
Soil Runoff
Typical Source of Contamination
Water additive used to control microbes
Typical Source of Contamination

Byproducts of drinking water disinfection

TABLE 2: UNREGULATED CONTAMINANTS
This table summarizes the monitoring results for unregulated contaminantsViolation?
Contaminant
Units
Highest Level Detected
Yes/NoSodium

NA

ppm

20

Limit
(MCL or MRDL)

Typical Source of Contamination

N/A

N/A

TABLE 3: UNDETECTED CONTAMINANTS4
This table summarizes the monitoring results for undetected contaminants
Inorganic Contaminants

Arsenic, Antimony, Barium, Beryllium, Cadmium, Chromium, Nickel, Selenium, Thallium, Fluoride, Mercury, Cyanide, Nitrite

Synthetic Organic Compounds

Dioxin. Heptachlor epoxide, Di(2-ethylhexyl)adipate, Di (2-ethylhexyl)phthalate, Hexachlorobenzene, Simazine, Alachlor, Atrazine, Propachlor,
Metribuzin. Butachlor, Aldrin, Benzo[a]pyrene, Metolachlor, gamma-BHC (Lindane), Dieldrin, Endrin, Methoxychlor, Heptachlor,
Hexachlorocyclopentadiene, Diquat, 1,2-Dibromoethane, 1,2-Dibromo-3-Chloropropane, PCB-1016, PCB-1221, PCB-1232, PCB-1242, PCB-1248
PCB-1254, PCB-1260, Chlordane (technical), Toxaphene, Glyphosate, EDB/PCBs/Glyphosate, 2,4,5-TP (Silvex), Dalapon, Dicamba, Dinoseb
Pentachlorophenol, Picloram, 2,4-D, Endothall, Aldicarb, Aldicarb sulfone, Aldicarb sulfoxide, Carbaryl, Carbofuran, 3-Hydroxycarbofuran, Methiocarb
Methomyl, 1-Naphthol, Oxamyl

Volatile Organic Compounds

Benzene, Carbon tetrachloride, o-Dichlorobenzene, cis-1,2-Dichloroethylene, trans-1,2-Dichloroethylene, 1,1-Dichloroethylene, 1,1,1-Trichloroethane
1,2-Dichloroethane, Dichloromethane, 1,1,2-Trichloroethane, 1,2,4-Trichloro-benzene, 1,2-Dichloropropane, Ethylbenzene, Monochlorobenzene,
para-Dichlorobenzene, Styrene, Tetrachloroethylene, Trichloroethylene, Toluene, Vinyl chloride, Xylene (total)

Perfluorooctanoic Acid (PFOA), Perfluorooctanesulfonic Acid (PFOS), 11-Chloroeicosafluoro-3-oxaundecan e-1-sulfonic acid, 1H,1H,2H,2HPerfluorodecane sulfonic acid (8:2 FTS), 1H,1H,2H,2H-Perfluorohexane sulfonic acid (4:2 FTS), 1H,1H,2H,2H-Perfluorooctane sulfonic acid (6:2 FTS),
4,8-Dioxa-3H-perfluorononanoic acid (ADONA), 9-Chlorohexadecafluoro-3-oxanonan e-1-sulfonic acid, Hexafluoropropylene Oxide Dimer Acid HFPODA), Perfluoro (2-ethoxyethane) sulfonic acid (PFEESA), Perfluoro (2-ethoxyethane) sulfonic acid (PFEESA), Perfluoro(4-methoxybutanoic acid),
Unregulated Contaminants
Perfluoro-3,6-dioxaheptanoic acid, Perfluoro-3-methoxypropanoic acid (PFMPA), Perfluorobutanesulfonic acid (PFBS), Perfluorobutanoic acid (PFBA),
Perfluorodecanoic acid (PFDA), Perfluorododecanoic acid (PFDoA), Perfluoroheptanesulfonic acid (PFHpS), Perfluoroheptanoic acid (PFHpA),
Perfluorohexanesulfonic acid (PFHxS), Perfluorohexanoic acid (PFHxA), Perfluorononanoic acid (PFNA), Perfluoropentanesulfonic acid, (PFPeS)
Perfluoropentanoic acid (PFPeA), Perfluoroundecanoic acid (PFUnA), N-ethylperfluorooctanesulfonamidoac etic acid (NEtFOSAA), Nmethylperfluorooctanesulfonamidoacetic acid (NMeFOSAA), Perfluorotetradecanoic acid (PFTeDA), and Perfluorotridecanoic acid (PFTrDA)
Notes: 1. Monitoring for Cryptosporidium and disinfectant contact times (i.e. CT values) is currently being performed and the results will be reported in 2024’s CCR.
2. TTHM and HAA5 results are based on the highest locational annual running average.
3. Lead and Copper Action Level is based on the 90th percentile value – i.e., no more than 10% of all sampled taps should exceed the AL.
4. Monitoring results for these analytes are based on samples taken in 2023, synthetic organic compounds were evaluated during 2021.

TABLE 4: VIOLATIONSMonitoring Violation
Failure to monitor for
Cryptosporidium

Failure to monitor forturbidity at specified
intervals

Explanation
Monitoring for Cryptosporidium, a microscopic
parasite, is required as a component of both, the
JEGS and the EPA’s Long-Term 2 Enhanced Surface
Water Treatment Rule (LT2ESWTR). Monitoring did
not occur in 2023 but is now taking place in 2024.
Turbidity is monitored, but not at the intervals
specified in both, the JEGS and the EPA’s Surface
Water Treatment Rule. For Public Water Systems
with two filters, the combined filter effluent must
be recorded at intervals of: (a) every 4 hours; andHealth Effects
Inadequately treated water may containdisease-causing organisms. These organisms
include bacteria, viruses, and parasites which
can cause symptoms such as nausea, cramps,
diarrhea, and associated headaches.
Turbidity has no health effects. However,turbidity can interfere with disinfection andprovide a medium for microbial growth.
Turbidity may indicate the presence ofdisease-causing organisms. These organisms
include bacteria, viruses, and parasites that

Steps Taken to Correct the Violation
In partnership with the Marine Corps, initialsampling for cryptosporidium was conductedstarting in February 2024, and will be reported aspart of next year’s CCR. Consumers do not needto take any further actions.
The Civil Engineering Squadron (CES) and Force
Support Squadron (FSS) units at Okuma are
currently working to determine a solution forincreasing the frequency of turbidity monitoring
to satisfy all requirements. Consumers do notneed to take any further actions.

(b) every 15 minutes. Currently, turbidity ismonitored only every 4 hours.

can cause symptoms such as nausea, cramps,
diarrhea and associated headaches.

ABBREVIATIONS & DEFINITIONS
Action Level (AL): The concentration of a contaminant which, if exceeded, triggers treatment or other requirements which a water system must follow.
ND: Not Detected
Maximum Contaminant Level (MCL): The highest level of a contaminant that is allowed in drinking water. MCLs are set as close to the MCLGs as feasible using the best available treatment
technology.
Maximum Contaminant Level Goal (MCLG): The level of a contaminant in drinking water below which there is no known or expected risk to health. MCLGs allow for a margin of safety.
Maximum Residual Disinfectant Level (MRDL): The highest level of a disinfectant allowed in drinking water. There is convincing evidence that addition of a disinfectant is necessary forcontrol of microbial contaminants.
Maximum Residual Disinfectant Level Goal (MRDLG): The level of a drinking water disinfectant below which there is no know or expected risk to health. MRDLGs do not reflect the benefitsof the use of disinfectant to control microbial contamination.
NA: Not applicable.
ppm: Parts per million or milligrams per liter (one part per million is equivalent to one penny in 10 thousand dollars).
ppb: Parts per billion or micrograms per liter (one part per billion is equivalent to one penny in 10 million dollars).
ppt: Parts per trillion or nanograms per liter (one part per trillion is equivalent to one penny in 10 billion dollars).
pCi/L: picocuries per liter, a common measure of radioactivity.
NTU: Nephelometric Turbidity Unit. A measure of the clarity of water. Turbidity in excess of 5 NTU is just noticeable to the average person.

Frequently Asked Questions
Why does the water sometimes look rusty?
Rusty or reddish tinted water may occur because of a sudden change inpressure due to flushing of a fire hydrant, etc. Iron causes the discolorationand is not a health risk. The normal flow of water will usually clear the mains
within two hours or less. Check your water by flushing a toilet three times
every 15 to 20 minutes. If you live on or near the end of a long distributionline, additional flushing may be required. Galvanized iron pipes or fittings
within a home or building may also cause discolored water. Running thewater will clear the piping system. If the hot water is rusty, the water heater
may need to be flushed.
What is a Boil Water Notice?
Any time a drop in pressure occurs from a water main break or system
maintenance, the Bioenvironmental Engineering Flight issues a Boil Water
Notice and immediate sampling requirements go into effect. Boil Water
Notices in these cases are precautionary and do NOT necessarily mean that
contamination has been detected or is suspected. In other cases, if coliform
is detected as part of our routine sampling program, a Boil Water notice will
also go into effect as a precaution while corrective measures are taken. In
this case, resampling continues until the corrective measures are completed.
Is it okay to drink from a garden hose?
The water supplied to the water hose is safe, but a garden hose is treated withspecial chemicals that can contain bacteria and other substances.
Will using a home water filter make the water safer or healthier?
Most filters improve the taste, smell and appearance of water, but they do notnecessarily make the water safer or healthier. If you use filters, please keep
in mind that they require regular maintenance and replacement. Failure to
perform maintenance and replacement can result in unsafe water.
What can I do to improve the quality of my drinking water?
Running the cold water tap for 30 seconds prior to use helps to flush out small
amounts of metals that may leach into water that has been sitting in metal
pipes overnight. Water used for consumption should always come from thecold-water tap. Hot water has a higher potential to leach metals into thewater.
How will I know if my water is not safe to drink?
Your water supplier must notify you if your water does not meet standards orif there is a waterborne disease emergency. The notice will describe any
precautions you need to take, such as boiling your water.
I don’t like the taste/smell/appearance of my tap water. What’s wrong
with it?
Even when water meets standards, you may still object to its taste, smell, or
appearance. Taste, smell and appearance are also known as aesthetic
characteristics and do not pose adverse health effects. Common complaints
about water aesthetics include: temporary cloudiness (typically caused byair bubbles) or chlorine taste (which can be improved by letting the water
stand exposed to the air).

Does the water system have a lead problem?
The Japan Environmental Governing Standards (JEGS) states 90 percent ofsamples must be below the action level. The water system met this criterion in
2023. The water system will continue to be sampled for lead, and the next
samples will be taken between June and September 2026. If present, elevatedlevels of lead can cause serious health problems, especially for pregnant womenand young children. Lead in drinking water is primarily from materials andcomponents associated with service lines and home plumbing. Okuma
Recreational Area is responsible for providing high quality drinking water but
cannot control the variety of materials used in plumbing components. When yourwater has been sitting for several hours, you can minimize the potential for lead
exposure by flushing your tap for 30 seconds to 2 minutes before using water for
drinking or cooking. If you are concerned about lead in your water, you may
wish to have your water tested. Information on lead in drinking water, testing
methods, and steps you can take to minimize exposure is available from the Safe
Drinking Water Hotline or at www.epa.gov/safewater/lead.
What are per- and polyfluoroalkyl substances and where do they comefrom?
Per- and polyfluoroalkyl substances (PFAS) are a group of thousands of manmade chemicals. PFAS have been used in a variety of industries and consumer
products around the globe, including in the U.S., since the 1940s. PFAS havebeen used to make coatings and products that are used as oil and water repellents
for carpets, clothing, paper packaging for food, and cookware. They are also
contained in some foams such as aqueous film-forming foam, or AFFF, used forfighting petroleum fires at airfields and in industrial fire suppression processes.
PFAS compounds are persistent in the environment, and some are persistent in
the human body – meaning they do not break down and they can accumulate
over time.
Is there a regulation for PFAS in drinking water?
In May 2016, the Environmental Protection Agency (EPA) established a lifetime
health advisory (LHA) level at 70 parts per trillion (ppt) for individual or
combined concentrations of perfluorooctanoic acid (PFOA) andperfluorooctanesulfonic acid (PFOS). Both compounds are types of PFAS. On
10 April 2024, the EPA published new drinking water standards for certain PFAS
under the Safe Drinking Water Act (SDWA). AF is reviewing the EPA’s newrule now, and will incorporate these standards into future sampling and analysis
efforts.
Out of an abundance of caution, DoD pursued PFAS testing and response actions
beyond EPA SDWA requirements. In 2020, the DoD established a policy tomonitor drinking water for 17 PFAS compounds at all service owned andoperated water systems. If results confirmed the drinking water contained PFOA
and PFOS at individual or combined concentrations greater than 70ppt, water
systems quickly took action to reduce exposures. While not a SDWA
requirement, n 2023, DoD improved upon its 2020 PFAS drinking water
monitoring policy by expanding the list of PFAS compounds monitored to 29,
implementing continued monitoring of systems with detectable PFAS over thelaboratory Method Reporting Limits (MRL), and requiring initial mitigation
planning actions.. Similarly in 2020, Japan set a temporary PFOA and PFOS
individual or combined target of 50 ppt.

Has Okuma tested its water for PFAS?
Yes. In November 2023, samples were collected at the Okuma water
treatment plant.. We are informing you that PFAS were not detected in yourwater system. Drinking water testing results were below the Method
Detection Limit (MDL) for all 29 PFAS compounds covered by the sampling
method, including PFOA and PFOS. In accordance with current DoD policy,
the water system will be resampled every two years for your continued
protection.
Is a Japanese translation of the CCR available? / CCR の⽇本語訳は⼊⼿可能ですか?
All sections of the CCR are written in English. Please contact the
Bioenvironmental Engineering Flight at 634-4752 for Japanese translation.
このレポートには、飲料⽔に関する重要な情報が含まれています。
誰かに翻訳してもらうか、理解できる⼈と話してください
弟１８航空医療中隊、生物環境工学部（BEF）は、沖縄にある空軍所有の施設及びその他の関連施設、更には基地内住宅の水道飲料水のモニタリングを空軍規則により行なっています。BEF はモニタリ
ングの水道水分析結果を消費者信頼度レポート（CCR)で利用者及び関係者に報告しています。
CCR の全てが英文訳の文書です。日本語訳希望者は BEF までご連絡下さい。基地内： 634-4752 基地外から：098-938-1111 ext. 634-4725

Where can I go for additional information?
This CCR will be posted on the Kadena AB homepage athttps://www.kadena.af.mil. Select About Us Tab, choose Consumer Confidence
Reports.
How can I get involved?
We encourage consumers to participate in decision-making events regarding
source water assessment and protection programs, for more information contact
Bioenvironmental Engineering at 634-4752.