2021 South Tahoe Public Utility District
CONSUMER CONFIDENCE REPORT 2021
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IS MY WATER SAFE?Yes.Last year,as in years Department of Public Health (CDPH). domestic wastewater discharges,oil and encourages our customers to attend,ask
past,your tap water met all U.S. You may view the document by visiting gas production,mining,or farming. questions,and provide feedback.
Environmental Protection Agency(EPA) the District's website at www.stpud.us or Pesticides and herbicides may come from
and state drinking water health standards. by requesting a copy by calling Customer a variety of sources such as agriculture, RESULTS OF RADON MONITORING Radon is a
The South Tahoe Public Utility District Service at 530-544-6474. urban stormwater runoff,and residential radioactive gas that cannot be seen,
vigilantly safeguards its water supplies,and The District has an ongoing drinking uses.Organic chemical contaminants, tasted,or smelled.It is found throughout
we are proud to report that our source water source development program that including synthetic and volatile organic the U.S.Radon can move up through the
water has not violated a maximum seeks potential drinking water well chemicals,are by-products of industrial ground and into a home through cracks
contaminant level or any other water locations.Due to the volume of the processes and petroleum production,and and holes in the foundation.Radon can
quality standard. average annual Sierra snowpack and can also come from gas stations,urban build up to high levels in all types of homes.
Some people may be more vulnerable Lake Tahoe itself,our aquifer has a stormwater runoff,agricultural application, Radon can also get into indoor air when
to contaminants in drinking water than significant recharge capability.The District and septic systems.Radioactive released from tap water from showering,
the general population.Immuno- continues to work diligently to protect and contaminants can be naturally occurring washing dishes,and other household
compromised persons such as persons maintain this precious natural resource. or be the result of oil and gas production activities.Compared to radon entering the
with cancer undergoing chemotherapy, and mining activities.In order to ensure home through soil,radon entering the
persons who have undergone organ WHY ARE THERE CONTAMINANTS IN MY that tap water is safe to drink,the United home through tap water will,in most cases,
transplants,people with HIV/AIDS or other DRINKING WATER?Drinking water,including States Environmental Protection Agency be a small source of radon in indoor air.
immune system disorders,some elderly, bottled water,may reasonably be (USEPA) and the California Department of Radon is a known human carcinogen.
and infants can be particularly at risk expected to contain at least small amounts Public Health (DPH) prescribe regulations Breathing air containing radon can lead to
from infections.These people should seek of some contaminants.The presence of that limit the amount of certain lung cancer.
advice about drinking water from their contaminants does not necessarily indicate contaminants in water provided by public Drinking water containing radon may also
health care providers.EPA/Centers for that water poses a health risk.More water systems.Food and Drug cause increased risk of stomach cancer.If
Disease Control (CDC) guidelines on information about contaminants and Administration (FDA) regulations establish you are concerned about radon in your
appropriate means to lessen the risk of potential health effects can be obtained limits for contaminants in bottled water home,test the air in your home.Testing is
infection by Cryptosporidium and other by calling the Environmental Protection which must provide the same protection inexpensive and easy.Fix your home if the
microbial contaminants are available Agency's (EPA) Safe Drinking Water Hotline for public health. level of radon in your air is 4 picocuries per
from the USEPA's Safe Water Drinking (1-800-426-4791).The sources of drinking liter of air(pCi/L) or higher.There are simple
Hotline (1-800-426-4791). water(both tap water and bottled water) HOW CAN I FIND OUT MORE?The information ways to fix a radon problem that aren't too
include rivers,lakes,streams,ponds, contained in the Consumer Confidence costly.For additional information,call your
WHERE DOES MY WATER COME FROM?There reservoirs,springs,and wells.As water Report may not answer all the questions state radon program or call EPA's Radon
are 11 active drinking water wells and 4 travels over the surface of the land or you may have about the quality of the Hotline (800-SOS-RADON).
standby wells which supply more than through the ground,it dissolves naturally South Tahoe Public Utility District's drinking
14,000 homes and businesses.All our occurring minerals and,in some cases, water supply.The District welcomes public RESULTS OF VOLUNTARY MONITORING
drinking water is pumped from radioactive material,and can pick up participation in developing water quality See data sheets.
underground aquifers.No water is taken substances resulting from the presence of policy.If you would like more detailed
from Lake Tahoe or any other surface animals or from human activity.Microbial information,please call the District REGARDING ARSENIC.Arsenic is a naturally
water source. contaminants,such as viruses and bacteria, Laboratory at 530-543-6231 or check our occurring substance that is sometimes
may come from sewage treatment plants, website at www.stpud.us. found at low levels in drinking water,
SOURCE WATER ASSESSMENT AND septic systems,agricultural livestock The District is governed by an elected particularly groundwater.The South Tahoe
PROTECTION The District's Groundwater operations,and wildlife.Inorganic five-member Board of Directors.Board Public Utility District has an active Arsenic
Management Plan (California Water Code contaminants,such as salts and metals, meetings are held on the first and third monitoring program,as well as a pilot
Section 10750)was adopted on December can be naturally occurring or result from Thursday of each month at 2 p.m.at the Arsenic removal system in one of its wells.
4,2014 and is on file with the California urban stormwater runoff,industrial,or Customer Service Facility located at 1275
Meadow Crest Drive.All meetings are open
to the public and the District
SPANISH(ESPANOL)Este informe contiene informacion muy importante sobre la calidad de su agua de beber.Por favor hagalo traducir o hable con alguien que to entienda bien.
WATER QUALITY DATA TABLE Ihe table below lists all presented in this table is from testing done in ADDITIONAL CONTAMINANTS In an effort to ensure IMPORTANT DRINKING WATER
of the drinking water contaminants which we the calendar year of the report.The EPA or the safest water possible,the State has required DEFINITIONS
detected which are applicable for the the State requires us to monitor for certain us to monitor some contaminants not required AL Allowed Limit:Limit for 90th
calendar year of this report.The presence of contaminants less often than once per year by Federal regulations.Of those contaminants percentile of samples.
contaminants in the water does not necessarily because the concentrations of these only the ones listed on the last page under
indicate that the water poses a health risk. contaminants do not change frequently. "Additional Contaminants"were found in your MCL Maximum Contaminant
Unless otherwise noted,the data water. Level:The highest level of a
contaminant that is allowed
in drinking water.MCLs are
MCLG/PHG OR MCL OR MRDL AVERAGE MIN MAX SAMPLE VIOLATION set as close to the MCLGs as
RADIONUCLEIDES MRDLG DATE TYPICAL SOURCE feasible using the best
Gross Alpha (pCi/L),minus Uranium 15 4.9 0.01 10.4 2020 No _m Decay and erosion of natural deposits available treatment
technology.
Uranium(pCi/L) 0.4 20 5.0 0.9 14.3 2021 No Decay and erosion of natural deposits MCLG Maximum Contaminant
Radium-226 (pCi/L) 0.05 ND ND 0.9 2019 No Erosion of natural deposits Level Goal:The level of a
Radium-228(pCi/L) 0.02 ND ND ND 2019 No 1 Erosion of natural deposits contaminant in drinking
water below which there is
Radon(pCi/L) NA 4,000 1330 305 3,930 2021 No Decay and erosion of natural deposits no known or expected risk to
VOLATILE ORGANIC CHEMICALS health.MCLGs allow for a
margin of safety.
MTBE[Methyl Teri Butyl Ether] (ppb) m 5 13 ND ND ND 2021 No Leaking underground storage tanks MRDL Maximum Residual
Disinfectant Level:The highest
Styrene(ppb) 100 100 ND ND ND 2021 No Discharge from factories.Leaching level of a disinfectant
from landfills allowed in drinking water.
Tetrachloroethylene(PCE) (ppb) i ND 5 ND ND ND 2021 No Discharge from factories,dry cleaners, There is convincing
and auto shops evidence that addition of a
disinfectant is necessary for
Toluene(ppb) 150 ND ND ND 2021 No Leaking underground storage tanks control of microbial
contaminants.
Xylenes(ppb) 1,750 ND ND ND 2021 No —1 Discharge from chemical factories.
Solvent MRDLG Maximum Residual
Total Trihalomethanes(ppb) NA 80 2.4 ND 7.3 2021 No Byproduct of drinking water level offian drinking
Level Goal: The
level a drink water
disinfection disinfectant below which
HaloAcetic Acids(ppb) I NA 60 ND ND ND 2021 No Byproduct of drinking water there is no known or
disinfection expected risk to health.
1,2,3-TCP(ppb) 0.0007 0.005 ND ND ND 2019 No Discharge from industrial and MRDLGs do not reflect the
f
agricultural waste.Leaching from benefits oof the use tr
disinfectants to control
hazardous waste sites. microbial contaminants.
MICROBIOLOGY PDWS Primary Drinking Water
A total of 1,087 Coliform and E.coli bacteria samples were taken throughout our distribution system,as part of our routine monitoring,in 2021. Standards:MCLs for
Total Coliforms(%Positive each 0 5 0 0 0 2021 No Naturally present in the environment. contaminants that affect
health along with their
month)
Source is warm blooded animals monitoring and reporting
E.coli(%Positive) 0 0 0 0 0 2021 No Human and animal fecal matter and requirements,and water
F wastes treatment requirements.
Heterotrophic Plate Count or HPC 200 NA 6 ND 127 2021 No Naturally present in environment PHG Primary Health Goal:The
(CFU) level of contaminant in
water
Chlorine,Free(ppm) 4 4 0.58 ND _ 1.8 2021 No thri el ig no
ere
wn r
Tem•erature-S stem °F NA 52 37 73 2021 No expected risk to health.
PHGs are set by the
California Environmental
LEAD AND COPPER—2020 MCLG/PHG AL 90TH SAMPLE #SAMPLES EXCEEDS Protection Agency.
AT CUSTOMERS'TAPS PERCENTILE DATE EXCEEDING AL AL TYPICAL SOURCE
Lead-action level ND 15 2.8 2020 0 No Corrosion of household plumbing
at consumer taps(ppb) systems Erosion of natural deposits
Copper-action ND 1,300 394 2020 0 No Internal corrosion of household
level at consumer plumbing systems;erosion of natural
taps(ppb) deposits;leaching from wood
preservatives
UNIT DESCRIPTIONS
PRIMARY INORGANIC STATE MCL AVERAGE MAXIMUM VIOLATION SAMPLE pg/L:Micrograms per Liter,or
CONTAMINANTS DATE COMMON SOURCE parts per billion
Aluminum ppb 1,000 ND ND No 2021 Erosion of natural deposits.Water treatment mg/L:Milligrams per liter or
Antimony ppb 6 ND ND No 2021 Discharge from Refineries,Soldering,Electronics parts per million
Arsenic ppb 10 3 9 No 2021 Glass and electronics production waste.Erosion ppm:Parts per million,or
Asbestos MFL 7 ND ND No 2015 Internal corrosion.Erosion of natural deposits milligrams per Liter(mg/L)
(fibers exceeding 0.01mm) ppb:Parts per billion,or
Barium ppb 1,000 12 48.1 No 2021 Oil drilling waste.Refineries.Erosion micrograms per Liter(pg/L)
Beryllium ppb 4 ND ND No 2021 Discharge from coal burning factories pCi/L:Picocuries per Liter(a
Cadmium ppb 5 ND ND No 2021 Internal corrosion.Erosion. Runoff from waste measure of radioactivity)
Chromium ppb 50 0.7 1.36 No 2021 Discharge from steel and pulp mills. Erosion MFL:Million Fibers per Liter,
Cyanide ppb 150 ND ND No 2021 Discharge from metal,fertilizer factories used to measure
asbestos concentration
Fluoride ppb 2,000 68 142 No 2021 Discharge from aluminum factories.Erosion NTU:Nephelometric Turbidity
Lead(at source) ppb 15 ND ND No 2021 Discharge from manufacturers. Erosion Units.Turbidity is a
Mercury ppb 2 ND ND No 2021 Runoff from landfills and factories.Erosion measure of the
Nickel ppb 100 ND ND No 2021 Discharge from metal factories.Erosion cloudiness of the water.
Nitrate as N ppm 10 0.24 0.59 No 2021 Runoff and leaching from fertilizer use.Septic tanks. CFU/ml:Colony Forming Units
Nitrite as N ppm 1 ND ND No 2021 Sewage spills.Erosion per milliliter
Perchlorate ppb 6 ND ND No 2021 Industrial discharge NA:Not Applicable
Selenium ppb 50 ND ND No 2021 Discharge from refineries.Runoff from livestock lots. ND:Not Detected
Thallium ppb 2 ND ND No 2021 Discharge from electronic and drug factories
SECONDARY INORGANIC
CONTAMINANTS
Alkalinity-Total ppm NA 52.6 64.6 No 2021 Erosion of natural deposits
Bromide ppm NA 0.01 0.04 No 2021 Erosion of natural deposits
Calcium ppm NA 14.6 21.0 No 2021 Erosion of natural deposits
Carbon Dioxide,Free ppm NA 3.6 15.1 No 2021 Naturally occurring
Chloride ppm 500 11.4 58.5 No 2021 Erosion of natural deposits
Color units 15 ND ND No 2021 Naturally occurring organic materials
Copper(at source) ppb 1,000 1.2 3.18 No 2021 Erosion of natural deposits
Dissolved Solids,Total ppm 1,000 100 192 No 2021 Erosion of natural deposits
Electrical Conductance pS/cm 1,600 139 287 No 2021 Erosion of natural deposits
Hardness ppm NA 44 72 No 2021 Erosion of natural deposits
Iron ppb 300 ND ND No 2021 Erosion of natural deposits
Magnesium ppm NA 2.6 6.4 No 2021 Erosion of natural deposits
Manganese ppb 50 ND 1.8 No 2021 Erosion of natural deposits
Odor-Threshold units 3 ND ND No 2021 Naturally occurring organic materials
ortho-Phosphate,as P ppm NA 0.04 0.14 No 2021 Erosion of natural deposits
Phosphorus-Total ppm NA 0.04 0.14 No 2021 Erosion of natural deposits
pH-after treatment units NA 8.1 7.2 and 9.5 No 2021 Erosion of natural deposits
Potassium ppm NA 1.2 4.6 No 2021 Erosion of natural deposits
Silver ppb 100 ND ND No 2021 Erosion of natural deposits
Sodium ppm NA 13 31 No 2021 Erosion of natural deposits
Sulfate ppm 500 3.5 5.7 No 2021 Erosion of natural deposits
Turbidity(NTU)The Turbidity NTU 5 0.13 0.35 No 2021 Soil runoff
limit for the highest single
measurement.
Vanadium ppb NA 1.7 3.8 No 2021 Erosion of natural deposits
Zinc ppb 5,000 ND ND No 2021 Runoff/leaching from natural deposits
SOCs (Synthetic Organic Compounds) are mostly human- SOC RESULTS AVERAGE MINIMUM MAXIMUM SAMPLE DATE
made carbon-based chemicals.They are used as pesticides, EPA 505 Or
defoliants,fuel additives and as ingredients in the anochlorine Pesticides/PCBs ND ND ND 7/2021, 11/2021
g
manufacture of many other compounds.Some of the more EPA 515.4-Chlorophenoxy Herbicides ND ND ND 7/2021, 11/2021
well-known ones include PCBs,Atrazine,Florene,Dioxins and
Caffeine.SOC's health effects include damage to the nervous EPA 551.1 -EDB/DBCP/HAN ND ND ND 7/2021, 11/2021
system and cancer risks.The District last tested for these
chemicals in 2021. EPA525.2-Semivolatiles ND ND ND 7/2021, 11/2021
EPA 548.1 -Endothall ND ND ND 7/2021, 11/2021
EPA 1613B-2,3,7,8-TCDD_Dioxin ND ND ND 7/2021, 11/2021
EPA 547-Glyphosate ND ND ND 7/2021, 11/2021
EPA 531.2-Aldicarbs ND ND ND 7/2021, 11/2021
EPA 549.2-Diquat and Paraquat ND ND ND 7/2021, 11/2021
EPA 524M-TCP-1,2,3-Trichloropropane ND ND ND 7/2021, 11/2021
ADDITIONAL MONITORING As part of an ongoing evaluation
program called UCMR (Unregulated Contaminant Monitoring UCMR-3 RESULTS ® AVERAGE MINIMUM MAXIMUM SAMPLE DATE
Rule),the Environmental Protection Agency requires the
District to monitor a number of additional contaminants/ Chlorate ppm 0.083 ND 0.440 2/2015
chemicals.Information collected through this monitoring
provides information for future decisions on drinking water Chromium,Total ppb 0.52 ND 1.30 2/2015
standards. Chromium-6 ppb 0.43 0.09 1.10 2/2015
UCMR-3 STPUD was required to monitor our source water for 28 Cobalt ppb ND ND ND 2/2015
chemical contaminants.The first round was completed in
August 2014 and the second round in February 2015.In the Molybdenum ppb 13.8 ND 65 2/2015
absence of identifiable industrial sources,these contaminants
are naturally occurring in our watershed.Chlorate is an Strontium ppb 124 15 330 2/2015
exception and is a degradation product of the disinfectant
used by the District for drinking water. Vanadium ppb 3.6 ND 13 2/2015
UCMR-4 In this round of UCMR,STPUD was required to monitor
for 18 chemical contaminants,as well as the Total Organic
Carbon (TOC) content in our Source Water.The first round was
completed in January 2019 and the second round in July
2019.These contaminants included metals like Germanium, UCMR-4 RESULTS ® AVERAGE MINIMUM MAXIMUM SAMPLE DATE
volatile Pesticides and their byproducts such as alpha-HCH,
volatile Alcohols like 1-Butanol and Tar/Oil byproducts like Total Haloacetic Acids HAA9 ppb 0.5 ND 4.2 1/2019,7/2019
Quinoline.
-
TOC ppm 0.3 ND 0.5 1/2019,7/2019
We also tested our Distribution System for 9 Disinfection
byproducts collectively known as Haloacetic Acids(HAA9). Germanium ppb ND ND ND 1/2019,7/2019
alpha-HCH ppb ND ND ND 1/2019,7/2019
Quinoline ppb ND ND ND 1/2019,7/2019
1-Butanol ppb ND ND ND 1/2019,7/2019