2003 UNIT DESCRIPTIONS IS MY WATER SAFE? Last year, as in years past, your tap WHY ARE THERE CONTAMINANTS IN MY DRINKING
ug/L:Parts per billion water met all U.S. Environmental Protection Agency (EPA) and WATER? Drinking water, including bottled water, may
mg/L: Number of milligrams of substance in state drinking water health standards. The South Tahoe Public reasonably be expected to contain at least small amounts of
one liter of water Utility District vigilantly safeguards its water supplies and, once some contaminants. The presence of contaminants does not
ppm:Parts per million,or milligrams per liter again, we are proud to report that our system has not violated a necessarily indicate that water poses a health risk. More
(mg/L) maximum contaminant level or any other water quality standard. information about contaminants and potential health effects can
ppb:Parts per billion,or micrograms per liter be obtained by calling the Environmental Protection Agency's
(Ng DO I NEED TO TAKE SPECIAL PRECAUTIONS? Some (EPA) Safe Drinking Water Hotline (800-426-4791). The sources
ppt: Parts per trillion,or nanograms per liter people may be more vulnerable to contaminants in drinking of drinking water (both tap water and bottled water) include
ppq: Parts per quadrillion,or picograms per water than the general population. Immunocompromised rivers, lakes, streams, ponds, reservoirs, springs, and wells. As
liter persons such as persons with cancer undergoing chemotherapy, water travels over the surface of the land or through the ground,
pCi/L:Picocuries per liter(a measure of persons who have undergone organ transplants, people with it dissolves naturally occurring minerals and, in some cases,
radioactivity) HIV/AIDS or other immune system disorders, some elderly, and radioactive material, and can pick up substances resulting from
mrem/yr:Millirems per year(a measure of
radiation absorbed by the body) infants can be particularly at risk from infections. These people the presence of animals or from human activity. Microbial
MFL:Million Fibers per Liter, used to measure should seek advice about drinking water from their health care contaminants, such as viruses and bacteria, may come from
asbestos concentration providers. EPA/Centers for Disease Control (CDC) guidelines on sewage treatment plants, septic systems, agricultural livestock
NTU:Nephelometric Turbidity Units.Turbidity appropriate means to lessen the risk of infection by operations, and wildlife. Inorganic contaminants, such as salts
is a measure of the cloudiness of the Cryptosporidium and other microbial contaminants are available and metals, can be naturally occurring or result from urban
water. We monitor it because it is a from the Safe Water Drinking Hotline (800-426-4791). stormwater runoff, industrial, or domestic wastewater discharges,
good indicator of the effectiveness of
our filtration system. oil and gas production, mining, or farming. Pesticides and
positive samples/month:The number of WHERE DOES MY WATER COME FROM?The District's herbicides, may come from a variety of sources such as
samples taken monthly that were found service area is organized into 16 pressure zones serving over agriculture, urban stormwater runoff, and residential uses.
to be positive 2.4 billion gallons annually from 16 active drinking water wells Organic Chemical Contaminants, including synthetic and
positive samples/yr:The number of positive to over 14,000 homes and businesses. All our drinking water is volatile organic chemicals, are by-products of industrial
samples taken that year pumped from underground aquifers. No water is taken from processes and petroleum production, and can also come from
%positive samples/month: Percentage of Lake Tahoe or anyother surface water source. gas stations, urban stormwater runoff, and septic
samples taken monthly that were systems.
p
positive Radioactive contaminants, can be naturally occurring or be the
%killed or inactivated: Percentage of SOURCE WATER ASSESSMENT AND ITS AVAILABILITY result of oil and gas production and mining activities. In order to
viruses/bacteria killed or inactivated by The District has an ongoing drinking water source development ensure that tap water is safe to drink, EPA and the state of
treatment method program to seek additional drinking water well locations. Due to California prescribe regulations that limit the amount of certain
CFU/ml:Colony Forming Units per milliliter the volume of the average annual Sierra snowpack and Lake contaminants in water provided by public water systems. Food
NA:Not Applicable Tahoe itself, our aquifer has a significant recharge capability. and Drug Administration (FDA) regulations establish limits for
ND: Not Detected The District continues to work diligently to protect and maintain contaminants in bottled water which must provide the same
NR: Not Required, but recommended this precious natural resource. protection for public health.
IMPORTANT DRINKING WATER HOW CAN I GET INVOLVED?The information contained in U.S. Radon can move up through the ground and into a home
DEFINITIONS the Consumer Confidence Report may not answer all the through cracks and holes in the foundation. Radon can build up
MCLG:Maximum Contaminant Level Goal:
The level of a contaminant in drinking questions you may have about the quality of the South Tahoe to high levels in all types of homes. Radon can also get into
water below which there is no known Public Utility District's drinking water supply. The District indoor air when released from tap water from showering,
or expected risk to health.MCLGs
allow for a margin of safety welcomes public participation in developing water quality and washing dishes, and other household activities. Compared to
MCL:Maximum Contaminant Level:The quantity policy. For more information, please call the District radon entering the home through soil, radon entering the home
highest level of a contaminant that is
allowed in drinking water.MCLs are set Information Office at 530-544-6474 extension 208. If you through tap water will, in most cases, be a small source of
as close to the MCLGs as feasible
using the best available treatment would like more detailed scientific information, please call the radon in indoor air. Radon is a known human carcinogen.
technology. District Laboratory at 530-544-6474 extension 231, or check Breathing air containing radon can lead to lung cancer.
PDWS:Primary Drinking Water Standards:
MCLs for contaminants that affect health our website at www.stpud.us Drinking water containing radon may also cause increased risk
along with their monitoring and of stomach cancer. If you are concerned about radon in your
reporting requirements,and water
treatment requirements. The District is governed by an elected five member Board of home, test the air in your home. Testing is inexpensive and easy.
AL:Action Level:The concentration of a Directors. Board meetings are held on the first and third Fix your home if the level of radon in your air is 4 picocuries per
contaminantgea which,or if exceeded, Thursdayof each month at 2:00p.m. at the CityCouncil liter of air (pCi/L) or higher. There are simple ways to fix a
triggers treatment or other requirements (p / ) g p
which a water system must follow.
Chambers located at 1900 Lake Tahoe Blvd. All meetings are radon problem that aren't too costly. For additional information,
PHG:Primary mi antHealth nGoal:n The level oel open to thepublic and the District encourages our customers to callyour state radon program or call EPA's Radon Hotline contaminant in drinking water below P 9 p g
(800-
below which there is no known or attend and become involved in the policy making process. SOS-RADON).
expected risk to health. PHGs are set
by the California Environmental
Protection Agency. WATER CONSERVATION PROGRAM Water is a precious RESULTS OF VOLUNTARY MONITORING See data sheets.
MRDLG:Maximum Residual Disinfection
Level Goal:The level of a drinking and finite resource in the Sierra. Due to the loss of a number of
water disinfectant below which there is drinking water wells due to contamination from MTBE, a motor ADDITIONAL INFORMATION FOR ARSENIC While your
no known or expected risk to health.
MRDLGs do not reflect the benefits of fuel additive, and the inordinately high cost of producing high- drinking water meets EPA's standard for arsenic, it does contain
microbialthe usb of disinfectants anns to control quality drinkingwater for landscape irrigation, it is crucial that low levels of naturallyoccurringarsenic. EPA's standard
contaminants. q �/ p g
MRDL:Maximum Residual Disinfectant Level: we irrigate in an efficient manner. Please call the Customer balances the current understanding of arsenic's possible health
The highest level of a disinfectant
allowed in drinking water.There is Service Department at 530-544-6474 if you would like specific effects against the costs of removing arsenic from drinking water.
convincing evidence that addition of a information on the District's Water Conversation Program. EPA continues to research the health effects of low levels of
disinfectant is necessary for control of
microbial contaminants. arsenic which is a mineral known to cause cancer in humans at
MNR:Monitored Not Regulated RESULTS OF RADON MONITORING Radon is a radioactive high concentrations and is linked to other health effects such as
MPL:Maximum Permissible Level as gas that you can't see, taste or smell. It is found throughout the skin damage and circulatory problems.
determined by the state of California
WATER QUALITY DATA TABLE CONTAMINANTS MCLG/PHG MCL OR AVG RANGE SAMPLE VIOLATION TYPICAL SOURCE
OR MRDLG MRDL LOW HIGH DATE
The table to the right lists all of the
drinking water contaminants that we INORGANIC CONTAMINANTS
detected that are applicable for the Arsenic(ppb) 0 50 7.5 ND 15.7 2003 No Erosion of natural deposits; Runoff
calendar year of this report.The from orchards; Runoff from glass and
presence of contaminants in the electronics production wastes
water does not necessarily indicate Fluoride(ppm) 1 2 0.1 ND 0.3 2003 No Erosion of natural deposits;Water
additive which promotes strong teeth;
that the water poses a health risk. Discharge from fertilizer and
Unless otherwise noted,the data aluminum factories
presented in this table is from testing Nitrate[measured as Nitrogen](ppm) 10 10 0.25 ND 0.94 2003 No Runoff from fertilizer use;Leaching
done in the calendar year of the from septic tanks,sewage; Erosion of
report. The EPA or the State natural deposits
requires us to monitor for certain Sodium(optional)(ppb) NA MPL 13.7 4.4 47.4 2003 No Erosion of natural deposits; Leaching
contaminants less than once per RADIOACTIVE CONTAMINANTS
year because the concentrations of Uranium(ug/L) 0 30 5 ND 21 2003 No Erosion of natural deposits
these contaminants do not change I
frequently. VOLATILE ORGANIC CONTAMINANTS
TTHMs[Total Trihalomethanes](ppb) NA 80 0.7 ND 0.7 2003 No By-product of drinking water disinfection
Tetrachloroethylene(ppb) 0.5 5 0.04 ND 1.4 2003 No Discharge from factories and dry cleaners
MICROBIOLOGICAL CONTAMINANTS
Turbidity(NTU)The TT limit is 5 NTU for the 2003 No Soil runoff
highest single measurement.Your water was 0.53.
MCLG/PHG AL AVG SAMPLE #SAMPLES EXCEEDS AL TYPICAL SOURCE
DATE EXCEEDING AL
INORGANIC CONTAMINANTS
Lead-action level at consumer taps(ppb) 0 15 6.3 2002 1 No Corosion of household plumbing systems;
Erosion of natural deposits
Copper-action level at consumer taps(ppb) 1.3 1.3 0.48 2002 4 No Corosion of household plumbing systems;
Erosion of natural deposits
ADDITIONAL CONTAMINANTS CONTAMINANT STATE MCL AVG VIOLATION EXPLANATION AND COMMENT
In an effort to insure the safest water Glyoxal NA 2 ug/L No By-product of MTBE treatment
possible the State has required us to Formaldehyde NA 6 ug/L No By-product of MTBE treatment
monitor some contaminants not Acetylaldehyde NA 2 ug/L No By-product of MTBE treatment
required by Federal regulations. Of Magnesium NA 2.6 mg/L No Erosion of natural deposits
those contaminants only the ones Calcium NA 11.5 mg/L No 'Erosion of natural deposits
listed to the right were found in your Potassium NA 1.5 mg/L No Erosion of natural deposits
water. Iron NA 56 ug/L No Erosion of natural deposits
Sulfate NA 3.7 mg/L No Erosion of natural deposits
Hardness NA 43.1 mg/L No Erosion of natural deposits
ortho-Phosphate NA 0.036 mg/L No ,Erosion of natural deposits
pH NA 7.6 Units No Erosion of natural deposits
Electrical Conductivity NA 154 No Erosion of natural deposits
Bromide NA 0.01 mg/L No Erosion of natural deposits
Alkalinity,Total NA 48 mg/L No Erosion of natural deposits
Total Phosphorus NA 0.04 mg/L No Erosion of natural deposits
Zinc 5000 ug/L 11.7 ug/L No -Erosion of natural deposits
Total Dissolved Solids 500 mg/L 104 mg/L No Erosion of natural deposits
Carbon Dioxide, Free NA 11.6 mg/L No Naturally occuring
UNREGULATED CONTAMINANT Total Organic Carbon NA 0.8 mg/L No
MONITORING Radon NA 890 pCi/L No
As part of an on-going evaluation Gross Alpha NA 2.8 pCi/L No Erosion of natural deposits
Manganese 50 ug/L 21.9 ug/L Yes Erosion of natural deposits
program the EPA has required us to
monitor some additional Chlorine Residual 4 mg/L 0.5 mg/L No By-product of disinfection process
contaminants/chemicals.
Information collected through the NAME REPORTED LEVEL LOW RANGE HIGH RANGE
monitoring of these MTBE 0 ND 0.47 ug/L
contaminants/chemicals will help to Perchlorate 0 ND 4 ug/I
ensure that future decisions on
drinking water standards are based Vanadium 0 ND 5 ug/L
on sound science. Boron 0 ND 700 ug/L