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Annual
Drinking Water Quality Report
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Gloucester County Public Utilities
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INTRODUCTION
This
Annual Drinking Water Quality Report for calendar year 2003 is designed to
inform you, the customer, about your drinking water quality. Our goal is to
provide you with a safe and dependable supply of drinking water, and we want
you to understand the efforts we make to protect your water supply. The
quality of your drinking water must meet state and federal requirements
administered by the Virginia Department of Health (VDH). Gloucester County
Public Utilities has not had any violations of a contaminant level or any
other water quality standard during the reporting year. Included in this
report are details about where your water comes from, what it contains and
how it compares to standards set by the EPA and VDH. Gloucester County
Public Utilities is committed to providing you with information about your
water supply, because customers who are well informed are our best allies in
supporting improvements necessary to maintain the highest drinking water
standards. If you have any questions about this report or any aspect of
your drinking water or want to know how to participate in decisions that may
affect the quality of your drinking water, please contact Lawrence A. Dame,
Director of Public Utilities, at (804) 693-4044 (ldame@gloucesterva.info).
GENERAL
INFORMATION
Drinking
water, including bottled drinking water, may reasonably be expected to
contain at least small amounts of some contaminants. The presence of
contaminants does not necessarily indicate that water poses a health risk.
More information can be obtained by calling the Environmental Protection
Agency’s Safe Drinking Water Hotline (800‑426‑4791).
The
sources of drinking water (both tap water and bottled water) include rivers,
lakes, streams, ponds, reservoirs, springs, and wells. As water travels
over the surface of the land or through the ground, it dissolves naturally
occurring minerals and, in some cases, radioactive material, and can pick up
substances resulting from the presence of animals or from human activity.
Contaminants that may be present in source water include: (1) Microbial
contaminants, such as viruses and bacteria, which may come from sewage
treatment plants, septic systems, agricultural livestock operations, and
wildlife. (2) Inorganic contaminants, such as salts and metals, which can
be naturally-occurring or result from urban stormwater runoff, industrial or
domestic wastewater discharges, oil and gas production, mining, or farming.
(3) Pesticides and herbicides, which may come from a variety of sources
such as agricultural, urban stormwater runoff, and residential uses. (4)
Organic chemical contaminants, including synthetic and volatile organic
chemicals, which are byproducts of industrial processes and petroleum
production, and can also come from gas stations, urban stormwater runoff,
and septic systems. (5) Radioactive contaminants, which can be naturally
occurring or be the results of oil and gas production and mining
activities. To ensure that tap water is safe to drink, EPA prescribes
regulations, which limit the amount of certain contaminants in water
provided by public water systems. Food and Drug Administration regulations
establish limits for contaminants in bottled water, which must provide the
same protection for public health.
Some
people may be more vulnerable to contaminants in drinking water that the
general population. Immuno-compromised persons such as persons with cancer
undergoing chemotherapy, persons who have undergone organ transplants,
people with HIV/AIDS or other immune system disorders, some elderly, and
infants can be particularly at risk from infections. These people should
seek advice about drinking water from their health care providers. EPA/CDC
guidelines on appropriate means to lessen the risk of infection by
cryptosporidium and other microbiological contaminants are available from
the Safe Drinking Water Hotline (800-426-4791).
Your
drinking water comes from two sources. The first is known as surface water,
which comes from the Beaverdam Reservoir. The water is treated at the
County’s water treatment plant. Your water treatment plant employs state of
the art technology which includes chemical coagulation, sedimentation and
filtration. Raw water is pumped from the Beaverdam Reservoir where
potassium permanganate and carbon are added. Potassium permanganate is used
to remove iron, organics and some manganese. Carbon is used to remove
color, organics and to control taste and odor. This water is pumped into a
mixing basin where alum and polymer are added for coagulation. The mixed
water is then drawn into vacuum chambers where it “pulsates” into our super
pulsator units, which separates large particles from the water. These large
particles are removed from the treatment process and disposed at the local
landfill. Settled water from the super pulsator is then filtered where
chlorine is first added for disinfection and manganese removal. The
filtered water is stored at the plant where it is pumped out into the
system. The second source of your drinking water comes from groundwater.
The County’s new Reverse Osmosis (RO) plant went into operation in April of
2003, and we began blending this water with the treated surface water from
two deep wells. These wells are approximately 1400 feet deep. The water is
then pumped to the RO plant where we first add the only chemical in the
process, an antiscalant that prevents fouling of the membranes used in the
process. Once at the plant, the well water passes through a series of sock
filters that remove tiny particles that may have been brought up from the
well. This also prevents the fouling of the membranes. After the filters,
high-pressure pumps are used to pump the water through the membranes used in
the reverse osmosis process. This removes dissolved solids from the
groundwater, leaving water that is nearly the same as bottled water. We
then pump the water over to the County’s clearwell, located at the surface
water plant where chlorine is added for disinfection and then pumped out
into the system for your use.
Under a
new program developed by VDH, a detailed source water assessment has been
conducted to find ways to better protect our water sources. This assessment
allows our staff, along with the VDH, to implement measures to reduce or
eliminate the sources of contamination.
As a first
step toward protection of our sources of drinking water, the Hampton Roads
Planning District Commission (HRPDC) and Virginia Department of Health (VDH),
evaluated the susceptibility of this water supply to contamination.
Contamination sources and pathways were reviewed using maps, known and
observed activities, water quality data and information about the water
source. Using criteria developed by the State in its EPA‑approved Source
Water Assessment Program, the following was determined:
Source
Susceptibility
i.
Beaverdam Reservoir High
ii.
Radial Well High
iii.
Birkhofer Well Low
This does
not mean that your drinking water is currently unsafe. Your current water
quality is described in the rest of this report. A copy of the source water
assessment report is available by contacting Mr. Lawrence A. Dame, Director
of Public Utilities, at (804) 693-4044.
DEFINITIONS
Contaminants
in your drinking water are routinely monitored according to
Federal and State regulations. The tables on the next
few pages show the results of our monitoring for calendar
year 2003. In the tables and elsewhere in this report
you will find many terms and abbreviations you might not be
familiar with. The following definitions are provided
to help you better understand these terms:
Non-detects (ND) - lab analysis indicates that the contaminant is not
present.
Parts
per million (ppm) or Milligrams per liter (mg/l) - one part per million
corresponds to one minute in two years or a single penny in $10,000.
Parts
per billion (ppb) Micrograms per liter - one part per billion corresponds
to one minute in 2,000 years or a single penny in $10,000,000.
Parts
per trillion (ppt) or Nanograms per liter (nanograms/l) - one part per
trillion corresponds to one minute in 2,000,000 years or a single penny in
$10,000,000,000.
Picocuries per liter (pCi/L) - picocuries per liter is a measure of the
radioactivity in water.
Action
Level (AL) - the concentration of a contaminant which, if exceeded,
triggers treatment or other requirements which a water system must follow.
Treatment Technique (TT) - a required process intended to reduce the level
of a contaminant in drinking water.
Maximum
Contaminant Level, or 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.
Secondary Maximum Contaminant Level, or SMCL - set recommended levels for
contaminants that affect water’s taste, color, odor or appearance.
Maximum
Contaminant Level Goal, or 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.
NTU (Nephelometric
Turbidity Unit) - the amount of turbidity in a water sample as measured by
the amount of light scattered by turbidity of the sample.
WATER
QUALITY RESULTS
I. Microbiological Contaminants
Contaminant |
MCLG |
MCL |
No. of Samples Indicating Presence of Bacteria |
Violation (Y/N) |
Month of Sampling |
Typical Source of Contaminant |
|
Total Coliform Bacteria |
0 |
5% of monthly samples are positive |
2 out of 41 or 4.9% |
N |
Nov. 2003 |
Naturally present in the environment |
II.
Contaminants Regulated at the Treatment Plant
Contaminant |
Ideal Goals EPA's MCLG |
Highest Allowable Level EPA's MCL |
Level Detected |
Typical Source of Contaminant |
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Aluminum |
|
_ |
<0.2 ppm |
Natural geology, mining |
|
Antimony |
6 ppb |
6 ppb |
<2 ppb |
Discharge from petroleum refineries,
soldering |
|
Arsenic |
N/A |
50 ppb |
<2 ppb |
Natural Geology, runoff from orchards |
|
Barium |
2 ppm |
2 ppm |
<0.2 ppm |
Natural geology, mining |
|
Beryllium |
4 ppb |
4 ppb |
<2 ppb |
Discharge from metal refineries, coal
burning |
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Cadmium |
5 ppb |
5 ppb |
<2 ppb |
Natural geology, corrosion of galvanized
pipes |
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Chromium |
100 ppb |
100 ppb |
<10 ppb |
Natural geology, discharge pump mills |
|
Cyanide† |
200 ppb |
200 ppb |
<10 ppb |
Discharge metal, plastic, fertilizer
factories |
|
Lead |
0 |
AL = 15 ppb |
<2 ppb |
Corrosion of household plumbing |
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Mercury |
2 ppb |
2 ppb |
<0.2 ppb |
Natural geology, runoff farms |
|
Nickel |
100 ppb |
100 ppb |
<10 ppb |
Natural geology |
|
Selenium |
50 ppb |
50 ppb |
<10 ppb |
Natural geology, discharge metal refinery |
|
Thalium |
2 ppb |
2 ppb |
<2 ppb |
Natural geology |
|
Nitrate/Nitrite-Nitrogen |
10 ppm |
10 ppm |
<0.05 ppm |
Natural geology, fertilizer runoff, septic
leachate |
|
Gross Alpha● |
0 |
15 pCi/L |
0.5 pCi/L |
Erosion of natural deposits |
|
Gross Beta● |
0 |
50 pCi/L |
1.2 pCi/L |
Decay of man-made products and natural
deposits |
|
Combined Radium● |
0 |
5 pCi/L |
0.7 pCi/L |
Erosion of natural deposits |
Samples were tested December 12, 2003. *Sample
tested in 1999. ●Samples tested in 2002.
Contaminant |
Ideal Goals EPA's MCLG |
Highest Allowable Level EPA's MCL |
Highest Detected |
Lowest Monthly Percentage of Samples Meeting the
Turbidity Limit |
Typical Source of Contaminant |
|
Turbidity |
N/A |
95% Below 0.3 NTU |
0.186 NTU |
99.8% |
Soil runoff |
|
Date |
- |
- |
1-08-2003 |
April 2003 |
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III. Other Contaminants Regulated in the Distribution
System
Contaminant |
Ideal Goals EPA's MCLG |
Highest Allowable Level EPA's MCL |
Highest Compliance |
Typical Source of Contaminant |
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Level |
Range |
|
Trihalomethanes (THM) |
0 |
80 ppb |
75 |
8-120 ppb |
Disinfection interaction |
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Haloacetic Acids (HAA) |
0 |
60 ppb |
60 |
0-85 ppb |
Disinfection interaction |
IV.
Contaminants Regulated at the Customer’s Tap
Contaminant |
Ideal Goals EPA's MCLG |
Highest Allowable level EPA's MCL (Action Level) |
90th Percentile |
Typical Source of Contaminant |
|
Lead** |
0 ppb |
15 ppb |
<5 ppb |
Customer's plumbing and service connection |
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Copper** |
1.3 ppm |
1.3 ppm |
0.311 ppm |
Customer's plumbing and service connection |
**Samples were collected last in September of 2001.
V.
Other Contaminants That Affect Taste, Odor and Appearance But Do Not Normally Affect the Health of Humans
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Contaminant |
SMCL |
Level Detected |
Source of Contaminant |
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Ammonia |
NL |
<0.04 ppm |
Natural geology |
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Chloride |
250 ppm |
28.1 ppm |
Minerals and Nutrients |
|
Copper |
1.3 ppm |
<0.2 ppm |
Natural geology |
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Fluoride |
2 ppm |
<0.2 ppm |
Natural geology |
|
Iron |
300 ppb |
<200 ppb |
Natural geology |
|
Manganese |
50 ppb |
<10 ppb |
Natural geology |
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Ortho-Phosphate |
NL |
0.03 ppm |
|
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Silica |
NL |
2.6 ppm |
Natural geology |
|
Sulfate |
250 ppm |
17.9 ppm |
Minerals and nutrients |
|
Sulfide |
NL |
<0.03 pm |
Minerals and nutrients |
|
Zinc |
5 ppm |
<0.2 ppm |
Natural geology |
|
pH |
8.5 Su |
7.67 Su |
|
|
Total Dissolved Solids |
500 ppm |
129 ppm |
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Samples were tested December 12, 2003.
We
constantly monitor for various contaminants in the water supply to meet all
regulatory requirements. The table lists only those contaminants that had
some level of detection. Many other contaminants have been analyzed but
were not present or were below the detection limits of the lab equipment.
The water quality results in the preceding tables are from testing done in
2003, unless otherwise noted. The state allows us to monitor for some
contaminants less than once per year because the concentrations of these
contaminants do not change frequently. Some of our data in tables II and IV,
though accurate, is more than one year old.
MCLs are
set at very stringent levels by the U.S. Environmental Protection Agency.
In developing the standards, EPA assumes that the average adult drinks 2
liters of water each day throughout a 70-year life span. EPA generally sets
MCLs at levels that will result in no adverse health effects for some
contaminants or a one-in-ten-thousand to one-in-a-million chance of having
the described health effect for other contaminants.
VIOLATION INFORMATION
There were
no MCL or TT violations during the year nor were there any monitoring,
reporting or other violations during the year for the Gloucester County
water system.
ADDITIONAL HEALTH INFORMATION
This
Drinking Water Quality Report was prepared by:
Lawrence A. Dame, Director of Public
Utilities
6582 Main Street
P.O. Box 329
Gloucester, Virginia 23061
804-693-4044
ldame@gloucesterva.info
A copy of
this report is also available by visiting the Gloucester County website at
www.gloucesterva.info
and accessing the “Services” page of the Public Utilities Department.
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