BUILDING PUBLIC TRUST
ing Water Standards
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Every year, all water suppliers that serve the same people year round
must prepare a consumer confidence report, or water quality report,
for their customers. The report tells customers where their drinking water
|f£%ja& and how they can protect it This booklet contains
mer confidence reports
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Contra Costa Water District's Open Door Policy
The Contra Costa Water District serves 450,000 people in
California's central and eastern Contra Costa County.
When water system officials produced the 2002
Consumer Confidence Report, they knew it was important
to their customers. So they included a section, "How to
Get Involved In the Quality of Your Water." The section
includes the times and places of water district board of
directors meetings and city council meetings, and
instructions for requesting agendas. The report also lists
names and phone numbers of contact people in each city
or water district population.
our customers Bet out of the tap every day-"
us weded to
The contact people listed in the report are not public information specialists, Oltman says. Rather, "They're
w er qua ty people at the plants, so callers are going directly to the source. They are talking to he peopTe
who sample and test the water. They are getting first-hand information" nspeopie
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Oilman says the Contra Costa Water District consistently has
public participation in meetings. In addition to listing meeting
info in the CCRs, they include a calendar in their newsletters and
other publications. Members of the public have responded by
calling and attending meetings. They raise issues of local
concern and even respond to news articles on national water
issues, such as conservation.
The district also published a Spanish-language report and plans
to do it again next year. The English-language CCR states how to
request copies and how to reach a bilingual staff member with
any questions. "It helps to have somebody speaking Spanish
answering the phone," Qltman says.
Regardless of language, what helps Contra Costa connect is a
personal touch. "We wanted people to feel comfortable calling
up and asking questions about their drinking water. When you
have somebody's name, you feel right off the bat more
comfortable picking up the phone and calling."
Ei Paso Water Utilities' Curious Customers
All drinking water contains naturally occurring minerals and other substances. Often, substances have no
harmful effects, but lead to interesting questions from the public.
"We receive a number of calls related to lithium," says John Balliew, water systems division manager of El
Paso Water Utilities. A small amount of lithium, a chemical sometimes used to treat mental illness, occurs
naturally in El Paso's water. Although the amount is much smaller than a medical dose, the lithium does
generate interest. "Periodically the newspaper will run an article," Balliew says. "There's speculation that it
corresponds with a low rate of violent crime here. People call up, even from other countries, saying they've
heard about it, is it correct?" . ,
To put it into perspective, the utility's 2002
Consumer Confidence Report has a Frequently Asked
Questions section that includes, "Is lithium present
in El Paso's Water? Does it have an effect on
people's moods?" The answer puts numbers into .
context. "To get the same amount of lithium as in
one standard capsule, you would have to drink about
600 glasses of water."
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Curious reporters and members of the public seem
to appreciate the information, Balliew says. "Most
people that have called in and talked to us about it
find it very helpful."
Another issue the Frequently Asked Questions sets
straight is the hardness of El Paso water. "The soft
water/hard water issue gets batted around a lot
because there are a lot of salespeople around selling
water .softeners," says Balliew. "Most people, if you
ask them, why do you have a water treatment
system, or buy bottled water, the number one
response is taste. 'Number two is hardness."
The OCR describes El Paso's water as "moderately hard to hard," based on. calcium and magnesium
content. The report explains that although excessively hard water can cause corrosion in pipes and cause
faster wear of certain appliances, the utility does not recommend that customers install water softeners.
"I think it helps the consumer save money," Baliiew says. "We're just trying to tell the consumer that they
should really think twice about accepting that type of information (from salespeople)."
Des Moiiies Water Works Promotes Prevention
In Iowa's Des Moines and Raccoon Rivers, nitrate contamination has been on an upward trend for nearly
three decades, reaching record levels in 2001. It's been a well-publicized issue, raising concern among
community members and prompting farmers to rethink their
practices. There have also been beach closings and warnings
not to swim in waters because of £ coli. So Des Moines
Water Works devoted its entire front page to source water
contamination and what people can do to prevent it.
"DMWW strongly believes that people need to understand the
problem before they can become part of the solution," says
Melissa Sharer of Des Moines Water Works' communications
staff. "DMWW tries to provide its customers with concrete
ideas for prevention strategies by explaining the source water
contaminants and then suggesting specific steps that can be
taken to prevent pollution."
The report explains how nitrates, bacteria and other
contaminants can enter ground water and surface water
sources, and describes how individuals can make a difference
at home and in the community. It also tells readers how to
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order copies of source water assessments. This information involves readers personally, enticing them to
turn the page and leam about the quality of their drinking water.
In addition to consumer confidence reports, Des Moines Water Works routinely educates customers
through its monthly newsletter, annual report, and various fact sheets distributed throughout the year.
Information is designed for all ages, from elementary schoolchildren to adult customers.
The education campaign has paid off. In a recent survey of its customers, Des Moines Water Works ranked
highest in terms of reliability regarding water quality and safety information sources. The utility ranked
ahead of-television, newspapers, government agencies, and health care professionals. Customers said they
appreciated that the information from the utility came from within, not an outside public relations company
repackaging the information with a positive spin. One respondent said the utility was "good in informing
public when, and if, there could be any problem in the quality of water."
United Water (Delaware: Honesty Wins Trust
United Water Delaware provides water services tb 103,000 people in New Castle County When a
treatment technique violation occurred in 2001, public water system officials immediately coordinated with
the health department and notified their consumers. The 2002 Consumer Confidence report included
detailed information about the turbidity violation. As required by the CCR regulation, it also included a clear
explanation of what happened, what actions were taken immediately to notify customers, locate and fix the
problem. The report explained that the turbidity had not interfered with disinfection/and there was
adequate chlorine residual to ensure that there was no risk to public health.
Plant manager Dave Fournier says that years ago, most public water system officials were reluctant to
disclose information on violations, wary of backlash from a frightened public. Today, with annual CCRs and
improved public notification requirements and customer relations,."there is much more focus on ethics and
reporting.
"There's a definite correlation between honesty and building public trust," Fournier says. "When something
does go wrong, they want to know if a utility is hiding anything. Our public perception is very important We
find it better to take a proactive approach, rather than sitting there waiting for the public to let us know."
In addition to reassuring customers, Fournier says the CCR is~a vehicle for encouraging them to think about
their environment and where their water comes from. For example, it helps them understand whether a
problem has originated at the treatment plant or pollution of the water source. "It might encourage them to
start thinking about.taking care of their water sources and environment."
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Consumer Confidence Report Major Requirements
Community Water Systems (CWS) with 15 or more connections or serving at least 25 year round residents
must prepare and distribute a OCR to all billing units or service connections.
April 1Deadline for CWS that sells water to another CWS to deliver the information necessary for
the buyer CWS to prepare their CCR (req. outlined in 40 CFR 141.152)
July 1Deadline for annual distribution of CCR to customers and State or local primacy agency for
report covering January 1 - December 31 of previous calendar year
October1(or 90 days after distribution of CCR to customers, whichever is first)Deadline for annual
submission of proof of distribution to State or local primacy agency
A system serving 100,000 or more persons must also post its current year's report on a publicly
accessible site on the Internet. Many systems choose to post their reports at the following EPA
website http://yosemlte.epa.gov/ogwdw/ccr.nsffamerica
All systems must make copies of the report available on request
Water System Information
Name/phone number of contact person
Information on public participation opportunities (time and place for meetings or hearings)
Information for non-English speaking populations (if applicable)
Source of Water
Type (ex. ground water or surface water), commonly used name, and location of water sources (ex.
Potomac River; Snake River Plain Aquifer, etc.) (Exact locations/coordinates of wells and intakes
should not be included for security reasons.)
Availability of source water assessment
Brief summary on potential sources of contamination (if available)
Definitions
Maximum Contaminant Level (MCL)
Maximum Contaminant level Goal (MCLG)
Treatment Technique (Tl) (if applicable)
Maximum Residual Disinfectant Level (MRDL) (|f applicable)
Maximum Residual Disinfectant Level Goal (MRDLG) (if applicable)
Action Level (AL) (if applicable)
Variances and Exemptions (if applicable)
Detected Contaminants
Table summarizing data on detected regulated and unregulated contaminants that were detected during
the last round of sampling
Known or likely source of each detected contaminant
Health effects language for any violations, exceedances or when Arsenic levels are > 0.010 mg/L or <,
0.05 mg/L ;
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Information on Cryptosporidium, Radon, and other contaminants (if applicable)
Compliance with Drinking Water Regulations
Explanation of violations, length of violations, potential health effects, and steps taken to correct the
violations '
Explanation of variance/exemption (if applicable)
Required Educational Information
Explanation of contaminants and their presence in drinking water including bottled water
Warning for vulnerable or immunocompromised populations about Cryptosporidium
Informational statements on arsenic, nitrate, lead, and TTHM (if applicable)
EPA'S Safe Drinking Water Hotline 1-800-426-4791 . .
Comparisons Help Readers Visualize Numbers
Often the measures used for detected contaminants are confusing to consumers. Terms such as one part
per million and one part per billion are hard to visualize and grasp. Consider using comparisons to explain
the contaminant amounts found in water:
Think of one part per million as:
1 inch in 16 miles
1 minute in 2 years
. 1 cent in $10,000
Think of one part per billion as: ; .
1 inch in 16,000 miles , ' '
1 second in 32 years .
' 1 cent in $10 million
Using these comparisons may help your customers understand the significance of a detected level in your
drinking water. : . .
V
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National Primary Drinking Water Standards
jj Contaminant *** ^ 1
w
^
."expolure atove the MCL' ',*"..
Common sources of * ,, v jhiMie. i
contaminant in drinking water; , Health Goal
Microorganisms
Cryptosporidium
Giardia lamblia
Heterotrophic plate
count (HPC)
TV
TT3
TT3
Gastrointestinal illness (e.g.,
diarrhea, vomiting, cramps)
- Gastrointestinal illness (e.g.,
diarrhea, vomiting, cramps)
HPC has no health effects; it is an
analytic method used to measure
Human and fecal animal waste zero
Human and animal fecal waste zero
HPC measures a range of n/a
bacteria that are naturally
the variety of bacteria that are
common in water. The lower
the concentration of bacteria in
drinking water, the better
maintained the water system is. '
present in the environment
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Vffwsr-*' ^ -5
eCflntanmrant MCiorTT1
E8i^^v'W)»
'.egionella TT3
Total Conforms 5.0%4
Including feca!
coliform and £ coli)
Potential health effects from
exposure above the MCL *",
Legionnaire's Disease, a type of
pneumonia
Not a health threat in itself; it is
used to indicate whether other
. potentially harmful bacteria may
be present5
^Common sources of J* >, Public
contaminant in drinking water ^ Hcnltli Goal1
Found naturally in water;
multiplies in heating systems
Coliforms are naturally present
in the environment as well as
feces; fecal conforms and
£ coli only come from human
and animal fecal waste.
zero
zero
Turbidity
TT3 Turbidity is a measure of the
cloudiness of water. It is used to
indicate water quality'and filtration
. effectiveness (e.g., whether
disease-causing organisms are
present). Higher turbidity levels are
often associated with higher levels
of disease-causing microorganisms
such as viruses, parasites and
some bacteria. These organisms
can cause symptoms such as
nausea, cramps, diarrhea, and
associated headaches.
Soil runoff
n/a
' PouiitiaJlwafo effects'from'*" 7"
exposure anove the MCL ^ _ _ ,i:
on sources of *w ~ "*~ Pottfe* ,
Health Goal
Viruses (enteric)
TT3
Gastrointestinal illness (e.g.,
diarrhea, vomiting, cramps)
Human and animal fecal waste
Disinfectants
Chloramines
(as CI2)
Chlorine
(asCI2)
MRDL=
4.0'
MRDL=
4.01
Eye/nose irritation; stomach
discomfort, anemia
Eye/nose irritation; stomach
discomfort
Water additive used to control
microbes
Water additive used to control
microbes
MRDLG
=41
MRDLG
=4'
Chlorine dioxide
(asCIOZ)
MRDL= Anemia; infants & young children:
0.8' nervous system effects
Water additive used to control MRDLG
microbes . =0.8'
Disinfection Byproducts
Bromate.
0.010 Increased risk of cancer
Byproduct of drinking water
disinfection
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'Contaminant
Chlorite
laloacetic acids
HAA5)
Total Trihalo-
methanes
TTHMs)
"'MCI or IT1
1.0
0.060 .
0.10
0.080
after
12/31/03
iPotentiafbeartfreffects from "*
exposure above the MCL ,
Anemia; infants & young children:
nervous system effects
Increased risk of cancer
Liver, kidney or central nervous
system problems; increased risk
of cancer
Common sources or :
contaminant in drinking water ,
Byproduct of drinking water
disinfection
Byproduct of drinking water
disinfection
Byproduct of drinking water
disinfection
Jullic '
Health Goal,
0.8
n/a6
n/a6
norganic Chemicals , ,
Antimony
0.006 Increase in blood cholesterol;
decrease in blood sugar
Discharge from petroleum
refineries; fire retardants;
ceramics; electronics; solder
0.006
Arsenic
0.0.10 Skin damage or problems with
as of circulatory systems, and may have
1/23/06 increased risk of getting cancer
Erosion of natural deposits;
runoff from orchards, runoff
from glass & electronics
production wastes
h Contaminant,
MCL or IT' Potential health effects from
exposure above the MCL
Barium
Common, sources of "* v Puttie ,
contaminant in drinking water Health Goaf
Asbestos 1 million Increased risk of developing benign Decay of asbestos cement in 7 MFL
(fibers > 10 fibers per intestinal polyps water mains; erosion of
micrometers) Liter (MFL) , . natural deposits
2 Increase in blood pressure
Discharge of drilling wastes;
discharge from metal refineries;
erosion of natural deposits
Beryllium
0.004 Intestinal lesions
Discharge from metal
refineries and coal-burning
factories; discharge from
electrical, aerospace, and
_ defense industries
0.004
Cadmium
0.005 Kidney damage
Corrosion of galvanized pipes;
erosion of natural deposits;
discharge from metal refineries;
runoff from waste batteries
and paints
0.005
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Chromium (total)
Copper
Cyanide (as free
cyanide)
Fluoride
Lead
Mercury (inorganic)
Nitrate (measured
as Nitrogen)
i^j^'*?^!^?^?^*^^^^^^^^*^"^^^^^^ U
0.1 Allergic dermatitis Discharge from steel and 0.1 I
pulp mills; erosion of natural 1
deposits I
TT7; Short term exposure: Gastro- Corrosion of household 1.3 1
Action intestinal distress. Long term plumbing systems; erosion
Level = exposure: Liver or kidney damage, of natural deposits
. 1.3 People with Wilson's Disease
should consult their personal
doctopif the amount of copper in
their water exceeds the action level
0.2 Nerve damage or thyroid problems Discharge from steel/metal , 0.2
factories; discharge from
plastic and fertilizer factories
4.0 Bone disease (pain and tenderness Water additive which promotes 4.0
of the bones); Children may get strong teeth; erosion of natural
mottled teeth deposits; discharge from
' fertilizer and aluminum factories
i/fctarTT' Pa'teniial health effects from , Common sources of Pubhe 1
(mg/L)z closure above the MCL contaminant in drinking water Health Goal
TT7; Infants and children:-Delays in Corrosion of household zero
Action physical or mental development; plumbing systems; erosion
Level = children could show slight deficits of natural deposits
0.015 in attention span and learning
abilities; Adults: Kidney problems;
high blood pressure
0.002 Kidney damage Erosion of natural deposits; ( 0.002
discharge from refineries and
factories; runoff from landfills
and croplands
10 Infants below the age of six Runoff from fertilizer use; 10
months who drink water containing leaching from septic tanks,
nitrate in excess of the MCL could sewage; erosion of natural
become seriously ill and, if deposits
untreated, may die. Symptoms
include shortness of breath and
blue-baby syndrome.
*
. \
..
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'*&-.
'i
. Contaminant . H/ICl or 1-T*
B8Jtf«*;'-''fr«ffl'
Nitrite (measured 1
as Nitrogen)
Potential health effects from
exposure above the MCL
Infants below the age of six
months who drink water
containing nitrite in excess of the
MCL could become seriously ill
and, if untreated, may die.
Symptoms include shortness of
breath and blue-baby syndrome.
Common sources of ^ _ Public
contaminant 10 drinking wafer Health Goal)
Runoff from fertilizer use; 1
leaching from septic tanks,
sewage; erosion of natural
deposits
Selenium 0.05 Hair or fingernail loss; numbness
in fingers or toes; circulatory
problems
Discharge from petroleum
refineries; erosion of natural
deposits; discharge from mines
0.05
Thallium
0.002
Hair loss; changes in blood; kidney,
intestine, or liver problems
Leaching from ore-processing 0.0005
sites; discharge from electronics,
glass, and drug factories
Organic Chemicals
Acrylamide
TT8
Nervous system or blood problems;
increased risk of cancer
Added to water during sewage/ zero
wastewater treatment
Potential health effects from.
5 * 'rfte-
contaminant in drinking water Health Goal
Alachlor
0.002 Eye, liver, kidney or spleen
problems; anemia; increased risk
of cancer
Runoff from herbicide used
on row crops
Atrazine
0.003
Cardiovascular system or
reproductive problems
Runoff from herbicide used on
row crops
0.003
Benzene
0.005 Anemia; decrease in blood .
platelets; increased risk of cancer
Discharge from factories;
leaching from gas storage
tanks and landfills
Benzo(a)pyrene
(PAHs)
0.0002 Reproductive difficulties; increased
risk of cancer
Leaching from linings of water
storage tanks and distribution
lines
Carbofuran
0.04
Problems with blood, nervous
system, or reproductive system
Leaching of soil fumigant used
on rice and alfalfa
0.04
Carbon tetrachloride 0.005 Liver problems; increased risk
of cancer
Discharge from chemical plants zero
and other industrial activities
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Ijnntaniinant
Chlordane
Chlorobenzene
2,4-D
Dalapon
1,2-Dibromo-3-
chloropropane
(DBCP) ,
IWM.orTT'
0.002
0.1
0.07
0.2
0.0002
Potential health effects, from
exposure above the MCL
Liver or nervous system problems;
increased risk of cancer
Liver or kidney problems
Kidney, liver, or adrenal gland
problems
Minor kidney changes
Reproductive difficulties;
increased risk of cancer
Common sources of < Public :'
contaminant in drinking water ' HealS Goaf
Residue of banned termiticide zero
Discharge from chemical and 0.1
agricultural chemical factories
Runoff from herbicide used on 0.07
row crops
Runoff from herbicide used on 0.2
rights of way
Runoff/leaching from soil zero
fumigant used on soybeans,
cotton, pineapples, and
orchards
o-Dichiorobenzene 0.6
Liver, kidney, or circulatory system Discharge from industrial
problems . chemical factories
0.6
fpGont9piiif9iii "" !
p-Dichlorobenzene
1,2-Dichloroethane
1,1-Dichloroethylene
cis-1,2-
Dichloroethylene
trans-1,2-
Dichloroethylene
Dichloromethane
1,2-Dichloropropane
MCI am'
0.075
0.005
0.007
0.07
0.1
0.005
0.005
1 Potential beaith.eflects from B
exposure sham the MCL
Anemia; liver, kidney or spleen
damage; changes in blood
Increased risk of cancer
Liver problems
Liver problems
Liver problems
Liver problems; increased risk
of cancer
Increased risk of cancer
Common sources of
contaminant in drinking: water
Discharge from industrial
chemical factories
Discharge from industrial
chemical factories
Discharge from industrial
chemical factories
Discharge from industrial .
chemical factories
Discharge from industrial
chemical factories
Discharge from drug and
chemical factories
Discharge from industrial
. chemical factories
" Public
Health Goal
0.075
zero
0.007
0.07
0.1
zero
zero
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Lpontaminant f ^
m$*$kvk%s£S^ i1*
Di(2-ethylhexyl)
adipate
Di(2-ethylhexyl)
phthalate
Dinoseb
Dioxin
(2,3,7,8-TCDD)
Diquat
Endothall
Endrin
ipichlorohydrin
Ethylbenzene
Ethylene
dibromide
ilyphosate
^ptachlor
ML at tt' Potential health effects from
, '- (mS/lj2 exposure above the MCL
0.4 Weight loss, liver problems, or
possible reproductive difficulties
0.006 Reproductive difficulties; liver
problems; increased risk of cancer
0.007 Reproductive difficulties
0.00000003 Reproductive difficulties;
increased risk of cancer
0.02 Cataracts
0.1 Stomach and intestinal problems
0.002 Liver problems
§^.VvT\tVi,>^-tw'i!;.i?.-toW'Bii'^^fc=a^fl^..^-u
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Hexachlorobenzene 0.001
Hexachlorocyclo- 0.05
pentadiene
Lindane 0.0002
Methoxychlor 0.04
Potential health effects from
exposure above the MCI
Liver or kidney problems;
reproductive difficulties;
increased risk of cancer
Kidney or stomach problems
Liver or kidney problems
Reproductive difficulties
Comujait sources, of Bunho j,
contaminant in drinking water Health Goal
Discharge from metal zero
refineries and agricultural
chemical factories
Discharge from chemical 0.05
factories '
Runoff/leaching from 0.0002
insecticide used on
cattle, lumber, gardens
Runoff/leaching from 0.04
insecticide used on fruits,
vegetables, alfalfa, livestock
Oxamyl (Vydate)
0,2 Slight nervous system effects
Runoff/leaching from
insecticide used on apples,
potatoes, and tomatoes
0.2
Pentachlorophenol
0.001 Liver or kidney problems;
increased cancer risk
Discharge from wood
preserving factories
' Picloram
0.5 Liver problems
Herbicide runoff
0.5
Polychlorinated 0.0005 Skin changes; thymus gland Runoff from landfills;
biphenyls (PCBs) problems; immune deficiencies; discharge of waste
reproductive or nervous system chemicals
difficulties; increased risk of
Simazine
0.004 Problems with blood
Herbicide runoff
0.004
Styrene
0.1
Liver, kidney, or circulatory
system problems
Discharge from rubber and
plastic factories; leaching
from landfills
0.1
Tetrachloroethylene 0.005 Liver problems; increased risk of
cancer
Discharge from factories and
dry cleaners.
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Toluene
Toxaphene
2,4,5-TP (Silvex)
1,2,4-
Trichlorobenzene
1,1,1-
Trichloroethane
1,1,2-
Trichloroethane-
i
' Trichloroethylene
Vinyl chloride
1 Nervous system, kidney, or liver
problems
0.003 Kidney, liver, or thyroid problems;
increased risk of cancer '
0.05 Liver problems
0.07 Changes in adrenal glands
0.2 Liver, nervous system, or
circulatory problems
0.005 Liver, kidney, or immune system
problems
t (BCLorTT1 Potential Health effects from k*f"
(mgll)2 exposure above the NIDI *
0.005 Liver problems; increased
risk of cancer
0.002 Increased risk of cancer
Discharge from petroleum
factories
Runoff/leaching from
insecticide used on cotton
and cattle
Residue of banned herbicide
Discharge from textile
finishing factories
Discharge from metal
degreasing sites and .
other factories
Discharge from industrial
chemical factories
Common sources of
contaminant in drinking water
Discharge from metal
degreasing sites and
other factories
Leaching from PVC pipes;
discharge from plastic
factories
1
zero
0.05
0.07
0.20
0.003
Health Goal
zero
zero
Xylenes (total)
10 Nervous system damage
Discharge from petroleum
factories; discharge from
chemical factories
10
Radionuclides
Alpha particles 15 Increased risk of cancer
picocuries
per Liter
(pCi/L)
Erosion of natural deposits of
certain minerals that are
radioactive and may emit a
form of radiation known as
alpha radiation
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Potential tiealth'Bffecfs from
j above the MCL
cnntpminant m drinking water Health Goal
Beta particles and 4 Increased risk of cancer
photon emitters millirems
per year
Decay of natural and man-
made deposits of certain
' minerals that are radioactive.
and may emit forms of
radiation known as photons
and beta radiation
Radium 226 and
Radium 228
(combined) '
5 pCi/L
Increased risk of cance?
Erosion of natural deposits
zero
Uranium 30 ug/L Increased risk of cancer,
as of ' kidney toxicity
12/08/03
Erosion of natural deposits
u,
Notes
1 Definitions ' ' .
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 and are non-enforceable public health goals.
Maximum Contaminant Level (MCL)The highest level of a contaminant that is allowed in drinking water. MCLs are set
as close to MCLGs as feasible using the best available treatment technology and taking cost into consideration. MCLs
are enforceable standards.
Maximum Residual Disinfectant Level Goal (MRDLG)The level of a drinking water disinfectant below which there is
no known or expected risk to health. MROLGs do not reflect the benefits of the use of disinfectants to control microbial
contaminants. '
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 for control of microbial contaminants:
Treatment Technique (TT)A required process intended to reduce the level of a contaminant in drinking water.
2 Units are in milligrams per liter (mg/L) unless otherwise noted. Milligrams per liter are equivalent to parts per million (ppmj.
3 EPA's surface water treatment rules require systems using surface water or ground water under the direct influence of
surface water to (1) disinfect their water, and (2) filter their water or meet criteria for avoiding filtration so that the
following contaminants are controlled at the following levels:
Cryptosporidium (as of1/1/02 for systems serving > 10,000 and 1/14/05 for systems serving <10,000) 99% removal.
Giardia lamb/is: 99.9% removal/inactivation
Viruses: 99.99% removal/inactivation . '' .
Legionalla: No limit, but EPA believes that if Giardia and viruses are removed/inactivated, Legionella will also be controlled.
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Turbidity: At no time can turbidity (cloudiness of water) go above 5 nephelolometric turbidity units (NTU); systems that
filter must ensure that the turbidity go no higher than 1 NTU (0.5 NTU for conventional or direct filtration) in at least 95%
of the daily samples in any month. As of January 1, 2002, for systems servicing > 10,000, and January 14,2005, for systems
servicing <10,000, turbidity may never exceed 1 NTU, and must^ot exceed 0.3 NTU in 95% of daily samples in any month.
HPC: No more than BOO bacterial colonies per milliliter
Long Term 1 Enhanced Surface Water Treatment (Effective Date: January 14,2005|; Surface water systems or (GWUDI) systems
serving fewer than 10,000 people must comply with the applicable Long Term 1 Enhanced Surface Water Treatment Rule provisions
(e.g. turbidity standards, individual filter monitoring, Cryptosporidium removal requirements, updated watershed control
requirements for unfiltered systems).
Filter Backwash Recycling: The Filter Backwash Recycling Rule requires systems that recycle to return specific recycle
flows through all processes of the system's existing conventional or direct filtration system or at an alternate location
. approved by the state.
4 No more than 5.0% samples total coliform-pdsitive in a month. (For water systems that collect fewer than 40 routine
samples per month, no more than one sample can be total coliform-positive per month.) Every sample that has total
coliform must be analyzed for either fecal conforms or E call if two consecutive TC-positive samples, and one is also
positive for E.coli fecal conforms, systetn has an acute MCI violation.
5 Fecal coliform and £ coll are bacteria whose presence indicates that the water may be contaminated with human or
animal wastes: Disease-causing microbes (pathogens) in these wastes can cause diarrhea, cramps, nausea, headaches,
or other symptoms. These pathogens may pose a special health risk for infants, young children, and people with severely
compromised immune systems.
6 Although there is no collective MCLG for this contaminant group, there are individual MCLGs for some of the individual
contaminants: . .
Halqacetic acids: dichloraacetic acid (zero); trichlorpacetic acid (0.3 mg/L)
Trihalomethanes: bromodichloromethane (zero); bromoform (zero); dibromochloramethane (0.06 mg/L)
7 Lead and copper are regulated by a Treatment Technique that requires systems to control the corrosiveness of their water.
If more than 10% of tap water samples exceed the action level, water systems must take additional steps. For copper, the
action level is 1.3 mg/L, and for lead is 0.015 mg/L.
8 Each water system must certify, in writing, to the state (using third-party or manufacturers certification) that when it uses
acrylamide and/or epichlorohydrin to treat water, the combination (or product) of dose and monomer level does not exceed
the levels specified, as follows: Acrylamide = 0.05% dosed at 1 mg/L (or equivalent); Epichlorohydrin = 0.01% dosed at
20 mg/L (or equivalent). . .. .
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National Secondary Drinking Water Standards
National Secondary Drinking Water Standards are non-enforceable guidelines regulating contaminants that may
cause cosmetic effects (such as skin or tooth discoloration) or aesthetic effects (such as taste, odor, or color) in
drinking water. EPA recommends secondary standards to water systems but does not require systems to comply.
However, states may choose to adopt them as enforceable standards.
I
Aluminum
Chloride '
Color
Copper
Corrosivity
Fluoride
Foaming Agents
Iron
Manganese
Odor
pH
Silver
Sulfate
Total Dissolved Solids
Zinc
0.05 to 0.2 mg/L
250 mg/L
15 (color units)
1.0 mg/L
noncorrosive
2.0 mg/L
^^
0.5 mg/L
0.3 mg/L
0.05 mg/L
3 threshold odor number
6.5-8.5
0.10fng/L
250 mg/L
500 mg/L
5 mg/L
X
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For More Information
EPA Office of Ground Water & Drinking Water
www.epa.gov/safewater
Safe Drinking Water Hotline * 1-800-426-4791
EPA/OGWDW (202) 564-3750
Office of Water (4606M) .
EPA 816-K-03-D03 June 2003
V.
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