2007 UNIT DESCRIPTIONS IS MY WATER SAFE? Last year, as in years past, your tap water, may reasonably be expected to contain at least small
water met all U.S. Environmental Protection Agency (EPA) and amounts of some contaminants. The presence of contaminants
ug/L:Parts per billion g Y
mg/L:Number of milligrams of substance in state drinking water health standards. The South Tahoe Public does not necessarily indicate that water poses a health risk.
one liter of water Utility District vigilantly safeguards its water supplies and, once More information about contaminants and potential health
ppm:Parts per million,or milligrams per liter again, we are proud to report that our system has not violated a effects can be obtained by calling the Environmental Protection
Img/LI maximum contaminant level or any other water quality standard. Agency's (EPA) Safe Drinking Water Hotline (1-800-426-4791).
ppb:Parts per billion,or micrograms per liter DO I NEED TO TAKE SPECIAL PRECAUTIONS? Some The sources of drinking water (both tap water and bottled water)
lug/0 people may be more vulnerable to contaminants in drinking include rivers, lakes, streams, ponds, reservoirs, springs, and
ppt:Parts per trillion,or nanograms per liter water than the general population. Immuno-compromised persons wells. As water travels over the surface of the land or through
ppq:Parts per quadrillion,or picograms per such as persons with cancer undergoing chemotherapy, persons the ground, it dissolves naturally occurring minerals and, in
liter who have undergone organ transplants, people with HIV/AIDS some cases, radioactive material, and can pick up substances
pCi/L:Picocuries per liter(a measure of or other immune system disorders, some elder) and infants can
radioactivity) YY resulting from the presence of animals or from human activity.
mrem/yr:Millirems per year(a measure of be particularly at risk from infections. These people should seek Microbial contaminants, such as viruses and bacteria, may
radiation absorbed by the body) advice about drinking water from their health care providers. come from sewage treatment plants, septic systems, agricultural
MFL:Million Fibers per Liter,used to measure EPA/Centers for Disease Control (CDC) guidelines on appropriate livestock operations, and wildlife. Inorganic contaminants, such
asbestos concentration means to lessen the risk of infection by Cryptosporidium and
NTU:Nephelometric Turbidity Units.Turbidityother microbial contaminants are available from the USEPA's as salts and metals, can be naturally occurring or result from
is a measure of the cloudiness of the Safe Water Drinking Hotline (1-800-426-4791). urban stormwater runoff, industrial, or domestic wastewater
water. We monitor it because it is a discharges, oil and gas production, mining, or farming.
good indicator of the effectiveness of WHERE DOES MY WATER COME FROM?The District's Pesticides and herbicides, may come from a variety of sources
our filtration system. service area is organized into 16 pressure zones serving over such as agriculture, urban stormwater runoff, and residential
positive samples/month:The number of 2.4 billion gallons annually from 14 active drinking water wells uses. Organic Chemical Contaminants, includingsynthetic and
samples taken monthly that were found to over 14,000 homes and businesses. All our drinkingis g
to be positive water volatile organic chemicals, are by-products of industrial
pumped from underground aquifers. No water is taken from
positive samples/yr:The number of positive processes and petroleum production, and can also come from
samples taken that year Lake Tahoe or any other surface water source. gas stations, urban stormwater runoff, agricultural application
%positive samples/month:Percentage of SOURCE WATER ASSESSMENT AND ITS AVAILABILITY and septic systems. Radioactive contaminants, can be naturally
samples taken monthly that were The District has an ongoing drinking water source development occurring or be the result of oil and gas production and mining
positive
program to seek additional drinking water well locations. Due to activities. In order to ensure that tap water is safe to drink, the
killed or inactivated:Percentage of the volume of the average annual Sierra snow pack and Lake
viruses/bacteria killed or inactivated by g P United States Environmental Protection Agency (USEPA) and the
treatment method Tahoe itself, our aquifer has a significant recharge capability. State Dept. of Health Services (DHS) prescribe regulations that
CFU/ml:Colony Forming Units per milliliter The District continues to work diligently to protect and maintain limit the amount of certain contaminants in water provided by
NA:Not Applicable this precious natural resource. public water systems. Food and Drug Administration (FDA)
ND: Not Detected WHY ARE THERE CONTAMINANTS IN MY regulations establish limits for contaminants in bottled water
NR: Not Required, but recommended DRINKING WATER? Drinking water, including bottled which must provide the same protection for public health.
IMPORTANT DRINKING WATER HOW CAN I GET INVOLVED?The information contained in the RESULTS OF VOLUNTARY MONITORING See data sheets.
DEFINITIONS Consumer Confidence Report may not answer all the questions you
MCLG:Maximum Contaminant Level Goal: may have about the quality of the South Tahoe Public UtilityDistrict's REGARDING ARSENIC Arsenic is a naturally occurring substance
The level of a contaminant in drinking that is sometimes found at very low levels in drinking water,
water below which there is no known drinking water supply. The District welcomes public participation in primarily groundwater. The U.S. Environmental Protection Agency
or expected risk to health.MCLGs developing water quality and quantity policy. For more information,
allow for a margin of safety. please call the District Information Office at 530-544-6474 (EPA) was required by the Safe Drinking Water Act Amendments of
MCL:Maximum Contaminant Level:The extension 6208. If you would like more detailed scientific 1996 to finalize a new drinking water standard for arsenic in
highest level of a contaminant that is
allowed in drinking water.MCLs are set information, please call the District Laboratory at 530-544-6474 2001 based on good scientific information and data.
as close to the MCLGs as feasible extension 6231, or check our website at www.stpud.us
using the best available treatment In September 2001, EPA adopted a new arsenic standard, or
technology. The District is governed by an elected five-member Board of maximum contaminant level (MCL), of 0.010 milligrams per liter or
PDWS:Primary Drinking Water Standards: Directors. Board meetings are held on the first and third Thursday of 10 parts per billion. This new standard went into effect on January
MCLsalong withfo contaminants monitoring ngt affect health each month at 2:00p.m. at the Customer Service Facilitylocated at 23, 2006. Water utilities are not immediatelydeclared out of
along their and
reporting requirements,and water 1 275 Meadow Crest Drive. All meetings are open to the public compliance or in violation of the new regulation. The federal
treatment requirements. and the District encourages our customers to attend and become regulation requires that water systems monitor for arsenic during the
AL:Action Level:The concentration of a lio o involved in the
contaminant which, if exceeded, p Y making process.
first 1-3 years to determine their official compliance levels. Once
triggers treatment or other requirements RESULTS OF RADON MONITORING Radon is a radioactive gas the monitoring is complete, a compliance determination is made.
which a water system must follow.
PHG:Primary Health Goal:The level of that you can't see, taste or smell. It is found throughout the U.S. The District is currently monitoring the affected wells.
contaminant in drinking water below Radon can move up through the ground and into a home through Since the California Department of Heath Services (DHS) remains at
below which there is no known or cracks and holes in the foundation. Radon can build up to high
expected risk to health. PHGs are set the prior MCL of 50 ppb, the federal standard of 10 ppb is now in
by the California Environmental levels in all types of homes. Radon can also get into indoor air effect in California. DHS is helping EPA to implement the federal
Protection Agency when released from tap water from showering, washing dishes,
MRDLG:Maximum Residual Disinfection and other household activities. Compared to radon entering the standard, but EPA is in charge of enforcing it. Once California
Level Goal:The level of a drinking home through soil, radon enteringthe home through tapwater will finalizes its standard, DHS will resume enforcement duties as well.
water disinfectant below which there is g g
no known or expected risk to health. in most cases, be a small source of radon in indoor air. Radon is a Of the District's fourteen active drinking water wells, two exceed the
MRDLGs do not reflect the benefits of known human carcinogen. Breathing air containing radon can lead new standard. Of those two wells, one has been disconnected from
the use of disinfectants to control
microbial contaminants. to lung cancer. Drinking water containing radon may also cause the water distribution system, however it could be placed into
MRDL:Maximum Residual Disinfectant Level: increased risk of stomach cancer. If you are concerned about radon temporary service in an emergency, such as fire. The remaining
The highest level of a disinfectant in your generally home, test the air in your home. Testing is inexpensive and well is utilized onlythe summer months.
allowed in drinking water.There is during
convincing evidence that addition of a easy. Fix your home if the level of radon in your air is 4 picocuries
disinfectant is necessary for control of per liter of air (pCi/L) or higher. There are simple ways to fix a The District anticipates completion of this treatment project by late
microbial contaminants. radon problem that aren't too costly. For additional information, 2009, and would then be in compliance with the federal standard.
MNR:Monitored Not Regulated call your state radon program or call EPA's Radon Hotline This compliance plan has been reviewed and approved by the
MPL:Maximum Permissible Level as (800-SOS-RADON). California Department of Pubilic Health (DPH).
determined by the state of California
WATER QUALITY DATA TABLE CONTAMINANTS MCLG/PHG MCL OR AVG RANGE SAMPLE VIOLATION TYPICAL SOURCE
The table to the right lists all of the OR MRDLG OR RNA DL LOW HIGH DATE
drinking water contaminants that we INORGANIC CONTAMINANTS
detected that are applicable for the Arsenic(ppb) 0 50 4.2 ND 18.0 2007 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 0.11 ND 0.31 2007 No Erosion of natural deposits;Water
that the water poses a health risk. additive which promotes strong teeth;
Unless otherwise noted,the data Discharge from fertilizer and
aluminum factories
presented in this table is from testing
done in the calendar year of the Nitrate[measured as Nitrogen](ppm) 10 10 0.26 0.01 0.95 2007 No Runoff from fertilizer use;Leaching
The EPA or the State from septic tanks,sewage; Erosion of
report.
natural deposits
requires us to monitor for certain Sodium(optional)(ppb) NA MPL 11.3 4.2 26.5 2007 No Erosion of natural deposits; Leaching
contaminants less than once per
year because the concentrations of RADIOACTIVE CONTAMINANTS
these contaminants do not change
Gross Alpha(pCi/L), minus Uranium 15 0.61 0.01 1.85 2007 No Erosion of natural deposits
frequently.
Uranium(pCi/L) 0.5 20 4.53 0.98 12.0 2007 No Erosion of natural deposits
VOLATILE ORGANIC CONTAMINANTS
MTBE[Methyl Tert Butyl Ether](ppb) 5 13 ND ND 0.40 2007 No Leaking underground fuel storage tanks
TTHMs[Total Trihalomethanes](ppb) NA 80 1.4 ND 4.8 2007 No Byproduct of drinking water disinfection
PCE[Tetrachloroethylene] 0.06 5 ND ND 1.2 2007 No Discharge from factories,dry cleaners,
and auto shops
MICROBIOLOGICAL CONTAMINANTS
Total Coliforms(%Positive each month) 5 0 0 0 2007 No
E. Coll(%Positive) 0 0 0 0 2007 No
Heterotrophic Plate Count or HPC (CFU) NA 1.1 ND 37.2 2007 No
Turbidity(NTU)The TT limit is 5 NTU for the 2007 No Soil runoff
highest single measurement.Your water was 0.55
MCLG/PHG AL AVG SAMPLE #SAMPLES EXCEEDS AL TYPICAL SOURCE
INORGANIC CONTAMINANTS DATE EXCEEDING AL
ADDITIONAL CONTAMINANTS Lead-action level at consumer taps(ppb) 0 15 15.8 2005 5 No Corosion of household plumbing systems;
Erosion of natural deposits
In an effort to insure the safest water
Copper-action level at consumer taps(ppb) 1.3 1.3 0.24 2005 3 No Internal corrosian of household plumbing
possible the State has required us to systems;erosian of natural deposits;
monitor some contaminants not leaching from wood preservatives
required by Federal regulations. Of
those contaminants only the ones
listed to the right were found in your CONTAMINANT STATE MCL AVG VIOLATION EXPLANATION AND COMMENT
water. Alkalinity,Total NA 50 mg/L No Erosion of natural deposits
Bromide NA 0.013 mg/L No Erosion of natural deposits
Calcium NA 11.2 mg/L No Erosion of natural deposits
Carbon Dioxide, Free NA 4.9 mg/L No Naturally occuring
Chloride 500 5.3 mg/L No Erosion of natural deposits
Chlorine Residual, Free 4 mg/L 0.42 mg/L No Byproduct of disinfection process
Dissolved Solids,Total 1,000 mg/L 88 mg/L No Erosion of natural deposits
Electrical Conductivity 1,600 127 No Erosion of natural deposits
Hardness NA 36.5 mg/L No Erosion of natural deposits
Iron 300 53.3 ug/L No Erosion of natural deposits
Magnesium NA 1.93 mg/L No Erosion of natural deposits
Organic Carbon,Total NA 0.22 mg/L No
ortho-Phosphate,as P NA 0.02 mg/L No Erosion of natural deposits
pH NA 7.95 Units No Erosion of natural deposits
Phosphorus,Total NA 0.03 mg/L No Erosion of natural deposits
Potassium NA 0.92 mg/L No Erosion of natural deposits
Radon NA 1,300 pCi/L No
Sulfate 500 3.77 mg/L No Erosion of natural deposits