HomeMy WebLinkAbout2004 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/LI 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
(ug ) 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: Lion absorbed per year(ameasurey) of infants can be particularlyat risk from infections. These people thepresence of animals or from human activity. Microbial
radiation by the body) p P
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 any other surface water source. gas stations, urban stormwater runoff, and septic systems.
samples taken monthly that were
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 RESULTS OF RADON MONITORING Radon is a radioactive
DEFINITIONS the Consumer Confidence Report may not answer all the gas that you can't see, taste or smell. It is found throughout the
MCLG:Maximum Contaminant Level Goal:
The level of a contaminant in drinking questions you may have about the quality of the South Tahoe U.S. Radon can move up through the ground and into a home
water below which there is no known Public Utility District's drinking water supply. The District through cracks and holes in the foundation. Radon can build up
or expected risk to health.MCLGs
allow for a margin of safety. welcomes public participation in developing water quality and to high levels in all types of homes. Radon can also get into
MCL:Maaxi t um level of arconatnt Levvel:Tat is he quantity policy. For more information, please call the District indoor air when released from tap water from showering,
hihesallowed in drinking water.MCLs are set Information Office at 530-544-6474 extension 6208. If you washing dishes, and other household activities. Compared to
as close to the MCLGs as feasible would like more detailed scientific please call the radon entering the home through soil, radon entering the home
using the best available treatmentinformation,
technology. District Laboratory at 530-544-6474 extension 6231, or check through tap water will, in most cases, be a small source of
PDWS:Primary Drinking Water Standards: radon in indoor air. Radon is a known human carcinogen.
MCLs for contaminants that affect health our website at www.stpud.us
along with their monitoring and Breathing air containing radon can lead to lung cancer.
reporting requirements,and water The District is governed by an elected five-member Board of Drinking water containing radon may also cause increased risk
treatment requirements. Directors. Board meetings are held on the first and third
AL:Action Level:The concentration of a g of stomach cancer. If you are concerned about radon in your
contaminant which, if exceeded, Thursday of each month at 2:00 p.m. at the City Council home, test the air in your home. Testing is inexpensive and easy.
wgghghrateamentoystemr other
mu requirements
t qu re ents Chambers located at 1900 Lake Tahoe Blvd. All meetings are Fix your home if the level of radon in your air is 4 picocuries per
icrw.
PHG:Primary Health Goal:The level of open to the public and the District encourages our customers to liter of air (pCi/L) or higher. There are simple ways to fix a
contaminant in drinking water below attend and become involved in the policy making process. radon problem that aren't too costly. For additional information,
below which there is no known or
expected risk to health. PHGs are set call your state radon program or call EPA's Radon Hotline (800-
by the California Environmental WATER CONSERVATION PROGRAM Water is a precious SOS RADON).
Protection Agency. and expensive resource in the Sierra. Due to the high cost of
MRDLG:Maximum Residual Disinfection
Level Goal:The level of a drinking producing water that meets California's stringent drinking water RESULTS OF VOLUNTARY MONITORING See data sheets.
water disinfectant below which there is standards for landscape irrigation use, it is very important we ADDITIONAL INFORMATION FOR ARSENIC While your
no known or expected risk to health.
MRDLGs do not reflect the benefits of irrigate in an efficient manner. For that reason, the following drinking water meets EPA's standard for arsenic, it does contain
the use of disinfectants to control i designated irrigation days have been established:
microbial contaminants. g g Y low levels of naturally occurring arsenic. EPA's standard
MRDL:Maximum Residual Disinfectant Level: • Even numbered addresses water Monday-Wednesday-Friday balances the current understanding of arsenic's possible health
The highest level of a disinfectant • Odd numbered street addresses water Sunda Tuesda Thursda
allowed in drinking water.There is Y Y Y effects against the costs of removing arsenic from drinking water.
convincing evidence that addition of a • No landscape irrigation on Saturday-it's our peak demand day EPA continues to research the health effects of low levels of
disinfectant is necessary for control of
microbial contaminants. For additional information, specific questions,or to obtain a copy arsenic which is a mineral known to cause cancer in humans at
MNR:Monitored Not Regulated of the Water Conservation program please call the Customer high concentrations and is linked to other health effects such as
MPL:Maximum Permissible Level as Service Department at 530-544-6474. 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 OR NL
drinking water contaminants that we INORGANIC CONTAMINANTS
detected that are applicable for the Arsenic(ppb) 0 50 5.4 ND 15.7 2004 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 2004 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 0.90 2004 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 16.5 4.7 73.0 2004 No Erosion of natural deposits; Leaching
contaminants less than once per RADIOACTIVE CONTAMINANTS
year because the concentrations of Uranium(ug/L) 0 30 7.8 ND 23.4 2004 No Erosion of natural deposits
these contaminants do not change
frequently. VOLATILE ORGANIC CONTAMINANTS
MTBE[Methyl Tert Butyl Ether](ppb) 5 13 ND ND 0.6 2004 No Leaking underground fuel storage tanks
TBA[Tert Butyl Alcohol](ppb) NA 12 ND ND 8.0 2004 No Leaking underground fuel storage tanks
TTHMs[Total Trihalomethanes](ppb) NA 80 0.7 ND 5.6 2004 No Byproduct of drinking water disinfection
Tetrachloroethylene(ppb) 0.5 5 0.04 ND 1.4 2004 No Discharge from factories and dry cleaners
MICROBIOLOGICAL CONTAMINANTS
Turbidity(NTU)The TT limit is 5 NTU for the 2004 No Soil runoff
highest single measurement.Your water was 0.55.
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 Aceylaldehyde NA 1.2 ug/L No Byproduct of MTBE treatment
possible the State has required us to
monitor some contaminants not Alkaliniy,Total NA 55 mg/L No Erosion of natural deposits
required by Federal regulations. Of Bromide NA 0.02 mg/L No Erosion of natural deposits
those contaminants only the ones Calcium NA 12.1 mg/L No Erosion of natural deposits
listed to the right were found in your
water. Carbon Dioxide, Free NA 23.6 mg/L No Naturally occuring
Chlorine Residual 4 mg/L 0.5 mg/L No Byproduct of disinfection process
Dissolved Solids,Total 500 mg/L 115 mg/L No Erosion of natural deposits
Electrical Conductivity NA 170 No Erosion of natural deposits
Formaldehyde NA 3.4 ug/L No Byproduct of MTBE treatment
Gross Alpha NA 1.6 pCi/L No Erosion of natural deposits
Hardness NA 47.4 mg/L No Erosion of natural deposits
Iron NA 55 ug/L No Erosion of natural deposits
Magnesium NA 2.9 mg/L No Erosion of natural deposits
Organic Carbon,Total NA 0.32 mg/L No
ortho-Phosphate NA 0.03 mg/L No Erosion of natural deposits
pH NA 7.8 Units No Erosion of natural deposits
Phosphorus,Total NA 0.04 mg/L No Erosion of natural deposits
Potassium NA 1.6 mg/L No Erosion of natural deposits
Radon NA 1,150 pCi/L No
Sulfate NA 3.7 mg/L No Erosion of natural deposits
Tert Butyl Alcohol NA <2 ug/L No Byproduct of MTBE treatment
Zinc 5000 ug/L 17.8 ug/L No Erosion of natural deposits