How Well Do You Know
Your Water Well?
Groundwater and Water Wells in Colorado
Prepared by:
Michael Matheson, P.G.; Plateau Environmental Services, Inc.
Joe Bowden, PhD; CDS Environmental Services, LLC
Copyright © 2011 Michael Matheson and Joe Bowden, All Rights Reserved.
In cooperation with the following agencies:
Colorado Division of Water Resources
Colorado Department of Public Health and Environment
Colorado Oil & Gas Conservation Commission
Agency Contacts
Colorado Division of Water Resources (CDWR)
303-866-3585
http://water.state.co.us/
Colorado Department of Public Health & Environment (CDPHE)
303-692-2000 or 1-800-886-7689 (in-state)
http://www.cdphe.state.co.us/
Colorado Oil & Gas Conservation Commission (COGCC)
303-894-2100
http://cogcc.state.co.us/
US EPA Safe Drinking Water
http://water.epa.gov/drink/
Information considered accurate as of October 2011
Table of Contents
Introduction
2
Aquifers and Water Use Basics
3-5
Water Well Permitting, Construction and Recordkeeping
6-7
Water Well Protection and Pollution Sources
8-9
Anatomy of a Water Well
10-11
Water Well Maintenance
12
Water Quality Standards and Interpretation
13-21
Water Treatment Decision Guide
22-23
Chlorination Techniques
24-26
Trouble Shooting Guide
27
Water Testing Glossary
28-31
Basic Well Data
32
Helpful Water Web Sites
Inside Back Cover
Agency Contacts
Inside Front Cover
1
Introduction
Due to the rural nature of much of
Colorado, individual domestic water
wells are a way of life for many of
us. This informative booklet has
been prepared as a reference guide
for private water well owners
throughout the state. In it you will
find basic information concerning
the groundwater that is supplied to
you from your private water well. It
includes information about:
•
the occurrence of groundwater
and different types of aquifers;
•
how recharge and use of
groundwater can affect the
amount and quality of water
available to you;
•
water well permitting and water
testing;
•
contamination sources and setbacks;
•
typical components of a water
well and distribution system;
•
water quality standards and test
result interpretation;
•
methane in groundwater;
•
information concerning well
maintenance and disinfection.
swer questions that this document
does not cover. People at these
agencies have a great deal of very
specific information about water
and wells. They may be able to help
Also included are some handy tools
you investigate and resolve prob-
such as a water well troubleshooting
lems or concerns that you may have.
guide, a water treatment decision
guide, a glossary of terms, and links
to helpful internet web sites that
deal with water issues.
It is our hope that you will keep this
guide handy and use it to record
information about your well and
answer basic questions about
Finally, the guide also contains con-
groundwater and your water well for
tact information for various gov-
years to come.
ernment agencies that can help an-
2
Aquifers and Water
Use Basics
Aquifers are porous and permeable
pore spaces. Rivers, streams and
exceed the recharge rate and
sediment or rock. Water is stored in
irrigation ditches can also recharge
groundwater levels in a given area
the small spaces between sediment
aquifers. When drought occurs, or
will decline. This is called “Ground-
or rock grains and particles and
irrigation water is removed, recharge
water Mining.”
moves very slowly through these
is diminished. Shallow river valley
interconnected “pore spaces”.
aquifers can be recharged quickly,
The figures below give an idea of
Groundwater can also be stored and
but recharge water may take many
how groundwater is found in differ-
move through small, interconnected
years to reach deep bedrock
ent types of rock. Sand and gravel
and naturally occurring fractures
aquifers.
can hold lots of water because pore
spaces are large and well con-
found in some rocks like sandstone,
granite, or shale. There is generally
Pumping groundwater from a well
nected. Sandstone has smaller
no such thing as “underground riv-
always causes a decline in ground-
pores that are less well connected
ers or lakes” except in rare and spe-
water levels at and near the well.
so it often yields less water. Shale
cial geologic conditions involving
This decline in groundwater level
has very small pores that are not
rocks known as limestone. Lime-
near the well also always causes a
interconnected; therefore, shales
stone aquifers are relatively rare in
diversion of groundwater from its
normally yield very little water. Coal
Colorado; however, Glenwood
natural, possibly distant area of dis-
can yield large amounts of water,
Springs is a example of groundwater
charge. Pumping of a single well
but will often contain some methane
discharged from a limestone aquifer.
typically has a local effect on the
gas and hydrogen sulfide. In some
groundwater-flow system. Pumping
areas, such as the Raton Basin near
Aquifers are replenished through a
of many wells (sometimes hundreds
Trinidad, Colorado, coal seams
process called “recharge.” Rain,
or thousands of wells) in large areas
found in shallow aquifers may be
snowmelt and even irrigation water
can have regionally significant ef-
the same coal seams where natural
all soak into the ground and slowly
fects on groundwater systems. Too
gas production occurs. However, in
move and accumulate to saturate
much groundwater pumping can
other areas, such as the San Juan
Basin near Durango, Colorado, the
natural gas industry removes methane from the thick coal seams,
sandstone and shale that are usually
several thousand feet deeper than
shallow aquifers. Crystalline rock
Sand and Gravel
(such as granite and limestone) has
Sandstone
no pores and water must be drawn
from interconnected naturally occurring fractures.
Shale and Coal
Crystalline Rock
3
Aquifers and Water Use Basics
Colorado water wells typically tap into five different kinds of aquifers.
River Valley Aquifer
River valley aquifers are found in shallow loose sediments
like gravel and sand next to rivers, streams and lakes.
They are usually of limited extent within the immediate
river or stream valley. These aquifers are recharged by
the river flow and usually have good water quality and
sustained yield because of the regular recharge from the
river or lake. However, the groundwater is often close to
the ground surface and is therefore very susceptible to
pollution from adverse surface conditions or septic sys-
River Valley Aquifer
tems.
Glacial Outwash Aquifer
Glacial outwash aquifers are thick accumulations of unconsolidated sand and gravel deposited over large areas
by alpine glaciers when they retreated many thousand
years ago. Many high terraces in valleys and plains adjacent to or near the mountains are covered with these
deposits. They are often developed areas for residences
and agriculture. Recharge to this aquifer type is primarily
from snowmelt, small mountain streams crossing to
larger rivers or irrigation water used on farms and
Glacial Outwash Aquifer
ranches. This aquifer type typically has good water quality and yield. However, as more water wells are drilled
and fewer farms are irrigated, the aquifer can become
depleted in certain areas.
Dune Field Aquifer
Large areas of the eastern plains of Colorado are covered
with wind deposited sand dunes that have been stabilized by vegetation. They are often called “Sand Hills.”
Rain, snowmelt and irrigation water have percolated into
these large accumulations of unconsolidated sand and
silt. The Sand Hills serve as an important shallow aquifer
Dune Field Aquifer
on the eastern plains. Water quality and yield from this
aquifer type can be good, but they are susceptible to
drought and groundwater mining.
4
Aquifers and Water Use Basics
Bedrock Shale and Sandstone Aquifer
Bedrock shale and sandstone aquifers are often tapped in
Colorado as these are the most common rock types in
developable areas outside the high mountains.
Most of
these aquifers are made up of interbedded layers of
sandstone and shale. More groundwater is generally
found in sandstone than in shale. The yield and quality of
water removed from bedrock aquifers can vary widely. In
some areas dominated by shale it may not be possible to
develop a well with good yield and water quality. And
Bedrock Shale and Sandstone Aquifer
because recharge into bedrock aquifers is usually very
slow, bedrock aquifers can easily suffer from the effects
of groundwater mining.
Crystalline Fractured Aquifer
Crystalline fractured aquifers are most commonly found
in mountain areas and include rocks such as granite,
metamorphic quartzite and volcanic rocks. Fractured
aquifers can also be found in areas with thick sandstone
or limestone deposits. While these types of rocks have
little or no pore spaces, groundwater can be stored and
transported in interconnected naturally occurring frac-
Crystalline Fractured Aquifer
tures among the rock. Wells that are drilled into a network of fractures can yield water. However, a nearby well
that does not intercept fractures may yield no water at all.
5
Water Well Permitting, Construction and Recordkeeping
The early stage of planning a new or
altogether unless a landowner ob-
land should always contact DWR
replacement water well includes
tains appropriate replacement water
before purchasing the property to
several steps. These steps include
rights. There are several areas in
determine if a well permit can be
selecting a licensed drilling and
Colorado that are designated as
issued for that particular parcel. It is
pump contractor, selecting a well
water critical areas. Persons inter-
also a good idea to contact a local
location that avoids contamination
ested in purchasing undeveloped
geologist to assist in evaluating the
hazards, and obtaining a well permit.
The Colorado Division of Water Re-
Sample Well Construction Report
sources requires that every new or
replacement well be permitted before it is drilled, and that water wells
must be drilled and constructed
pursuant to Colorado Water Well
Construction Rules (2 CCR 402-2).
http://water.state.co.us/DWRIPub/D
ocuments/constructionrules05.pdf
In general, the well permit application asks for ownership and proposed well location information,
proposed construction details, water
use and septic system information
and the well driller's license number.
http://water.state.co.us/groundwater
/wellpermit/Pages/default.aspx
The Division of Water Resources
(DWR) has several different types of
possible well permits that can be
issued. DWR form GWS-44 is used
for most residential and livestock
water wells. Based on certain water
rights criteria the DWR may limit
water to indoor use only for parcels
of less than 35 acres, and to outdoor
use of no more than 1 irrigated acre
for parcels larger than 35 acres. In
water critical areas (where water
rights are over appropriated) the
DWR may deny a new well permit
6
Water Well Permitting, Construction and Recordkeeping
probability of developing a good
As part of the well drilling process,
Keep these records in a safe place.
well on the parcel.
the driller must record certain data
You will need to refer to these
that will be reported to DWR. This
documents in the future when per-
Another early step in the well drilling
includes a record of the geologic
forming well maintenance or while
process is planning for your water
formations penetrated (the well
evaluating well problems. Always
analysis and treatment. In Colorado,
log), an as-built well construction
keep detailed records of any main-
private well owners are responsible
record and diagram, and an accu-
tenance or testing that is performed
for the quality and quantity of their
rate water level and well yield test.
on the well.
water supply. They are also respon-
It is very important that the driller
sible for determining what treat-
collects and records this information
A section is provided in the back of
ment equipment may be necessary
accurately. You may wish to ask the
this booklet that lets you record
for their well water. Before drilling a
driller to collect and save samples of
some of the basic construction and
new well or sampling your existing
all the different soil and rock forma-
permit information for your well for
well, you should contact a qualified
tions that were penetrated so that
your easy future reference.
analytical laboratory to discuss the
they can be examined later by a
appropriate analytical testing to be
geologist. You will also want the
performed on your well water. You
licensed driller and pump installer to
can obtain a list of qualified labora-
provide you with copies of all the
tories by contacting the Colorado
diagrams and reports that must be
Department of Public Health and
submitted to DWR.
Environment (CDPHE).
(http://www.cdphe.state.co.us/wq/d
rinkingwater/PrivateWellInformation.
html).
Have the water from your new well tested by a
qualified analytical laboratory. Record the results for
future reference.
Also, you should obtain the necessary bottles and instruction on how
to collect and preserve the water
If you have an existing well with no
sample. Then, after the well is
records, DWR can provide you with
drilled, fully developed and disin-
copies of the reports that were
fected you will be ready to collect
submitted by the driller when the
your water sample and deliver it to
well was drilled. You can find permit
the laboratory. Based on the ana-
and basic construction information
lytical results, you can select appro-
about the well at the DWR web site
priate treatment equipment (see
Well Permit Search function
Water Treatment Decision Guide on
(http://www.dwr.state.co.us/WellPer
page 18).
mitSearch/default.aspx). This web
site will have all of the available
scanned documents that have been
submitted for your well.
7
Water Well Protection and Pollution Sources
Man-Made Pollutants
Groundwater pollution occurs when
man-made products such as gasoline, oil, road salts, fertilizer, and
chemicals get into the groundwater
1
2
3
4
5
6
and cause it to become unsafe or
unfit for human use. Some of the
most common sources of pollutants
are leaking fuel storage tanks, septic
systems, animal holding pens (corrals), inappropriate chemical storage
sites, landfills, and the widespread
Common Man-Made Pollutants
use of road salts and agricultural
groundwater causing serious prob-
up in the groundwater if they are
chemicals. In general, keep these
lems. A permit is required to install,
improperly applied.
facilities and materials as far away
alter or repair a septic system in
from your water well as possible. If
Colorado (5 CCR 1003-6), and the
possible, your well should be placed
property owner is responsible for
waste into soil and neutralize
uphill of any potential contaminant
proper installation and maintenance
many types of contaminants.
source.
of the system and for abatement of
However, a septic system should
any nuisance arising from its failure.
be at least 100 feet from a water
A domestic well can easily be pol-
Contact your local or regional health
well and chemicals should not
luted if it is not properly constructed
department for more information on
be poured down the drain as
or if unsafe materials are released
local septic system rules (including
these may not be effectively
into the well. Toxic materials spilled
design and setbacks).
neutralized by the soil.
1.
Septic systems leach household
or dumped near a well can leach
2.
Fuel tanks and fueling opera-
into the aquifer and pollute the
Landfills are another source of pollu-
groundwater drawn from that well,
tion. When properly constructed,
tions can be a source of con-
making polluted wells used for
contemporary landfills have a pro-
tamination of groundwater if
drinking water very dangerous.
tective bottom layer to prevent pol-
there are leaks or spills. This
lutants from getting into our
can happen with both above-
Individual septic systems, or those
groundwater. But, if this protective
ground and underground tanks
not connected to a city sewer sys-
layer fails, pollutants from the landfill
and pipelines. Do not store fuel
tem, can also be a serious pollution
can make their way down into the
or transfer fuel near a water
source. Septic systems are de-
groundwater.
well. Fix leaks and cleanup spills
signed to slowly drain away human
immediately.
waste underground at a harmless
Finally, chemicals including fertiliz-
rate. An improperly designed, lo-
ers, insecticides and pesticides are
cated, constructed, or maintained
washed into the ground by irrigation
and improper chemical use can
septic system can leak bacteria, vi-
and precipitation and eventually end
all be sources of groundwater
3.
Chemical storage, leaks or spills
contamination. Typical chemi-
ruses, or household chemicals into
8
Water Well Protection and Pollution Sources
cals stored in a household may
trained professionals can re-
Natural Contaminants
include paint, solvents, fertilizer,
spond to correct the problem.
Contamination of groundwater is
herbicides, pesticides, cleaners
4.
not always a result of the introducLandfills can be a source of con-
tion of pollutants by human activi-
as instructed on the label. Do
taminants that can leach into
ties. Possible natural contaminants
not store or use chemicals near
groundwater. All current mu-
include trace elements such as arse-
(or in the same building as) your
nicipal and county landfills must
nic and selenium, dissolved gases
water well. Fix leaks and
meet stringent requirements for
like methane and radon, and high
cleanup spills immediately.
construction and monitoring.
concentrations of commonly occur-
However, historic landfills and
ring dissolved salts.
and oil. Always use chemicals
6.
Animal holding pens (corrals)
private “ranch” landfills can be
tend to become areas of con-
an unmonitored source of con-
In Colorado, many groundwaters
centrated animal waste. Rain
taminants. If you have a private
naturally contain arsenic, chloride,
water and snowmelt can carry
landfill then only place inert ma-
dissolved salts, fluoride, iron, mag-
these wastes into groundwater.
terials in it. Do not dispose of
nesium, manganese, selenium, sul-
Do not situate animal holding
chemicals, petroleum products
fate, radon, uranium, and other trace
pens near your water well. Use
and other potential contami-
metals in concentrations exceeding
a minimum 100 foot offset as
nants in private landfills. Infor-
recommended or mandatory stan-
you should with your septic sys-
mation concerning disposing of
dards for public drinking water es-
tem. Also, do not bury a dead
your own solid waste on your
tablished by the CDPHE, the U.S.
animal within 150 feet of a water
own property is available from
EPA and the U.S. Public Health
well (preferably further).
CDPHE at:
Service.
http://www.cdphe.state.co.us/h
5.
Oil and gas production facilities
m/onesownwaste.pdf
can be a source of contaminants such as oil, condensate
and produced water. Oil and
gas facilities must be sited a
minimum of 150 feet from residences and other occupied
structures. Keep your water
well at least that far from an oil
& gas production facility. Also, if
you notice anything leaking
from an oil & gas facility immediately call the operator of the
facility (there should be a sign
at the facility with an emergency contact number) so that
9
Anatomy of a Water Well
Typical Water Well Components
components are shown and labeled.
Knowing about the different com-
This schematic diagram represents a
The following list of water well terms
ponents of a water well, and their
typical water well as constructed in
helps explain the well components
function, will allow you to more ef-
a water table type aquifer. While
and other useful terms.
fectively discuss your well with your
most wells are much deeper than
licensed well driller or pump installer.
illustrated here, all of the individual
Sanitary Well Cap
Cables to Control Box
Pitless Adapter
Surface Casing
Drop Pipe
Cement
Electric Cables
Well Casing
Pumping Water Level
Well Screen
Gravel Pack
Submersible Pump
End Cap
10
Anatomy of a Water Well
Typical Water System Terminology
Aquifer – A water bearing layer of sediment or rock with interconnected pore spaces or fractures that can store and
deliver water to a well.
Borehole – The cylindrical hole drilled into the ground and aquifer.
Casing – Steel or PVC tubing placed in the borehole to keep the borehole open and to allow room to store water and
install a pump.
Casing Stickup – The amount of casing that sticks up above the ground surface. This should be at least 1 foot.
Cement – Placed between the wall of the borehole and the casing and surface casing to prevent surface contamination from reaching the aquifer.
Cistern – A water holding tank, usually underground, used for storage or treatment of water before being delivered to
the pressure tank and home. A cistern will usually be vented to allow gases such as methane and radon to escape.
Control Box – Electrical switch box that turns the well pump on and off.
Drop Pipe – Pipe placed in the casing to connect the pump to the surface.
Electrical Cable – Wiring from the pump control box to the pump that supplies power and command signals.
End Cap – Cap placed on the bottom of the casing to prevent sediment from flowing into the casing.
Gravel Pack – Gravel or sand placed between the borehole wall and the well screen to keep the borehole open and
filter water before it enters the well.
Groundwater – Water stored beneath the surface of the earth that is transmitted through small, interconnected pores
and fractures in sediment and rock.
Pitless Adapter – A device placed in the well casing that allows water to be diverted from the drop pipe to piping on
the exterior of the well below the frost line.
Pressure Tank – A water holding tank equipped with an air bladder that regulates water pressure into the home and
demand to the pump.
Pumping Water Level – The depth below the ground surface of the water level in the well when the pump is operating.
This is always deeper than the static water level.
Sanitary Well Seal – A sealed cap on the top of the well casing that prevents surface contaminants from entering the
inside of the well. It is also vented to allow gases such as methane and radon to escape the casing.
Submersible Pump – The most common type of water well pump includes the pump and pump motor placed at the
bottom of the drop pipe below the pumping water level.
Static Water Level – The depth below ground surface of water when the pump is not operating. This level will vary
seasonally and over longer time periods due to recharge, drought or groundwater mining.
Surface Casing – Steel casing at least 20 feet deep that is the first casing installed in a well that prevents surface contaminants from entering the well.
Treatment Equipment – Can include a variety of equipment designed to remove various water contaminants and purify groundwater before use.
Well Screen – Steel or PVC perforated pipe that water from the aquifer flows through to enter the well and pump.
11
Water Well Maintenance
other materials around the well.
9.
Keep your well records in a safe
place. These include the construction report, as well as annual water well system maintenance, water testing results, routine measurements of well yield
and static water level. A section
Properly constructed private water
3.
is provided in the back of this
Keep livestock, hazardous
supply systems require routine main-
chemicals, such as paint, sol-
tenance. These simple steps will
vents fertilizer, pesticides, herbi-
help protect your system and in-
cides, fuel and motor oil far
vestment.
away from your well and pump
booklet where you may record
basic information about your
well.
10. Be aware of changes in your
well, the area around your well,
house.
1.
Always use licensed water well
when a well is constructed, a
casing to ensure it is in good
pump is installed, a cistern is
repair and the vent is clear.
5.
Always maintain proper separa-
iced. Always ask to have a copy
tion between your well and
of their license or certification
buildings, waste systems,
and insurance before they start
chemical storage facilities and
any work on your well or system
livestock corrals.
or before you sign any contract.
6.
Do not allow back-siphonage.
A reputable professional will
When mixing pesticides, fertiliz-
gladly ask their insurance carrier
ers or other chemicals, do not
to provide you a certificate of
put the hose inside the tank or
insurance at no charge.
container.
An annual well maintenance
7.
When landscaping, keep the top
of your well at least one foot
try and bacterial test, a check of
above the ground. Slope the
the static water level, and a well
ground away from your well for
source of drinking water should
proper drainage.
8.
11.
A licensed water well contractor
or pump installer can periodically measure the water level in
your well and its production
rate. They can also clean your
well screen if there are indications of it becoming plugged by
mineralization or bacteria. The
pump installer can also clean
and maintain your cistern if you
have one.
12. When your well has come to the
end of its serviceable life (usu-
check, including a water chemis-
yield test is recommended. Any
or the water it provides.
Periodically check the well cover
or well cap on top of the well
installed, or the system is serv-
2.
4.
drillers and pump installers
Take care in working or mowing
be checked any time there is a
around your well. A damaged
change in taste, odor or appear-
casing could jeopardize the
ance, or anytime a water supply
sanitary protection of your well.
system is serviced.
Do not pile snow, leaves, or
12
ally more than 20 years), have
your licensed well driller properly plug and abandon your well.
Water Quality Standards and Interpretation
Interpreting Your Water Test
naturally occurring constituents and
following glossary of water testing
Report
pollutants or contaminants (if
terms, may assist you in
Obtaining a water analysis from a
present), most water testing
understanding a water analysis
testing laboratory is a necessary
laboratories provide little additional
report for some common
first step toward solving household
explanation of test results beyond
household water contaminants.
water quality problems. Before
the units used and possibly a
What Do the Numbers Mean?
testing, you may have
had concerns about
Once a water
the safety of the
testing laboratory
water used in the
has completed the
household. Or, you
analysis of your
may have noticed
water, you will
objectionable
receive a report. It
symptoms when
will contain a list of
using the water for
the natural
drinking, cooking, or
constituents,
other household
possible
purposes. Perhaps
contaminants and
you have routinely
physical
monitored your
characteristics for
household water
which your water
quality through
was tested and the
periodic testing and
measured
have recently noticed
concentration of
differing results
each. The
between tests for
concentration is
one or more
the amount of a
indicators. To
given substance
identify the source of
(weight) in a
contamination
specific amount of
problems, as well as
water (volume).
to determine the
The most common
type of corrective
concentration unit
action to take, a
used is milligrams
properly interpreted
water analysis report
per liter (mg/L)
Sample Water Quality Analysis Report
which, is
footnote or similar comment in the
approximately equal to one part per
event that a problem contaminant
million (ppm), or one part
Besides providing a laboratory
is identified. The information
contaminant to one million parts
report of the analysis for the
provided below, along with the
water.
is essential.
13
Water Quality Standards and Interpretation
How Much is too Much?
Acceptable limits for evaluating the
common household water quality
"Pure" water does not exist in nature
suitability and safety of your well
contaminants. These are divided
and all natural water contains some
water are established for many
into three categories: general indica-
dissolved mineral and salt constitu-
contaminants. Some established
tors, nuisance impurities, and health
ents. In most cases, the levels of
standards are set by nuisance
contaminants. (Note: Some con-
these naturally occurring constitu-
considerations (taste, odor, staining,
taminants are evaluated on the basis
ents are beneficial or minimal and of
etc.) while many are based on
of both nuisance and health criteria.)
little consequence. However, when
health implications and are legally
certain constituent levels in house-
enforceable with respect to public
hold water are excessive, they may
water systems. These acceptable
affect household activities and/or
limits should be used as guidelines
be detrimental to human, animal
for your own water supply when
and plant health. Evaluating what
evaluating your well water test
levels of constituents are acceptable
results.
and understanding the nature of
problems caused when the concen-
Whether you have the results of
tration is excessive and would be
tests that you specifically requested,
considered a contaminant of con-
or you simply instructed the labora-
cern are the basic considerations in
tory to conduct general or routine
interpreting a household water
household water quality tests, you
analysis report.
can use the following tables as a
general guideline for the most
14
Water Quality Standards and Interpretation
General Indicators
vegetation, and all warm-blooded
tine analysis (as often as once a
General water quality indicators are
animals. A positive total coliform
year) for most rural water supplies,
parameters used to indicate the
bacteria test result may be followed
unless there is a reason to suspect
possible presence of harmful con-
by tests for fecal coliform or E. coli
other contaminants.
taminants. Testing for indicators
bacteria which, if present, would
may eliminate the need for costly
confirm that sewage or animal
tests for specific contaminants.
waste is contaminating the water.
Generally, if an indicator is excessive,
Total dissolved solids (TDS) and pH
the water supply may contain other
are considered general water quality
contaminants as well, and further
indicators, and may vary over time
testing is recommended. For exam-
depending on well recharge charac-
ple, you are probably familiar with
teristics. The tests listed in Table 1,
coliform bacteria. These harmless
along with a test for nitrate/nitrite
bacteria are present in the air, soil,
(see Table 4), provide a good rou-
Table 1: General Water Quality Indicators
Indicator
Acceptable
Limit
Bacteria
None Present
Possible bacterial or viral contamination from human sewage, animal waste,
surface water or any one of a number of bacteria such as sulfate reducing,
slime formers, iron, methanogenic, etc..
pH Value
6.5 to 8.5
An important overall measure of water quality, pH can alter corrosivity and
solubility of contaminants. Low pH will cause pitting of pipes and fixtures
and/or metallic taste. This may indicate that metals are being dissolved. At
a high pH, the water will have a slippery feel or soda taste.
Total
Dissolved
Solids (TDS)
500 mg/L*
Dissolved minerals, like sodium, calcium, magnesium, iron or manganese.
High TDS also may indicate excessive hardness (scaly deposits) and cause
iron or mineral staining, or a salty, bitter taste.
Indication
Odor/Color
Can be indicative of high mineral content such as iron (red staining) or
manganese (black staining). Rotten egg odor is indicative of hydrogen sulfide. Both color and odor indicate that your water should be tested.
Gas Bubbles
Can be indicative of dissolved gas such as methane. Sometimes is indicative of low water levels and air being trapped by the pump.
* TDS levels greater than 500 mg/l are found naturally in many water wells and public drinking water systems in the western states.
Water with higher than 500 mg/l may cause mild and transient gastric upset and still be safe to drink. In many cases it is the only
source of water.
15
Water Quality Standards and Interpretation
Nuisance Impurities
poses. Nuisance impurities may
come from the EPA Secondary
Nuisance impurities are another
include iron, bacteria, chloride, and
Drinking Water Standards for public
category of contaminants. While
hardness. Table 2 lists some typical
drinking water systems.
these have no adverse health effects
nuisance impurities you may see on
at low levels, they may make water
your water analysis report. Accept-
unsuitable for many household pur-
able limits for nuisance impurities
Table 2: Common Nuisance Impurities and Their Effects
Contaminant
Acceptable
Limit
Chlorides
250 mg/L
Salty or brackish taste; corrosive; blackens and pits stainless steel and can
cause green plants to yellow.
Copper (Cu)
1.3 mg/L
Blue-green stains on plumbing fixtures; bitter, metallic .
Iron (Fe)
0.3 mg/L
Metallic taste; discolored beverages; yellowish stains on laundry, reddish
brown stains on fixtures.
Manganese (Mn)
0.05 mg/L
Black specks on fixtures; bitter taste.
Sulfates (S04)
250 mg/L
Bitter, medicinal taste; corrosive; may cause gastric upset and diarrhea.
Effects
Iron Bacteria
Orange to brown-colored slime in water, can cause an oil-like film on standing water, black-brown sludge in toilet tank.
Slime Bacteria
Jelly-like slime deposits in toilet tank, bottom of cisterns.
Sulfate Reducing
Bacteria
Rotten egg or sewer-like like smell.
Zinc (Zn)
5 mg/L
Zinc is an essential element in our diet. Too little zinc can cause problems,
but too much zinc is also harmful. Indication of galvanized pipe corrosion in
older homes.
16
Water Quality Standards and Interpretation
Water Hardness
used exclusively as a hardness unit
Hardness is one contaminant you
and equals approximately 17 mg/L
will also commonly see on the re-
or ppm. Those water supplies falling
port. Hard water causes white, scaly
in the hard-to-very hard categories
•
increased life of hot water
heater elements;
•
increased potential for pipe corrosion, and:
•
deposits on plumbing fixtures and
may need to be softened. However,
cooking appliances and decreased
as with all water treatment, you
cleaning action of soaps and deter-
should carefully consider the advan-
gents. Hardness is the sum of the
tages and disadvantages of soften-
Since the levels of sodium and po-
calcium and magnesium levels
ing before making a decision on
tassium can affect your health, con-
found in your water. Hard water can
how to proceed.
sult your health professional about
negative impact on houseplants.
any impacts that softening your wa-
also cause buildup in hot water
heaters and reduce their effective
Advantages and disadvantages of
ter may have on your health. If you
lifetime. Table 3 will help you inter-
softening your water include:
have a heart condition or high blood
pret your water hardness parame-
•
increased levels of sodium or
pressure you must consult your
potassium (depending on which
health professional before drinking
type of salt is used in your sof-
softened water.
ters.
Hardness may be expressed in either milligrams per liter (mg/L) or
grains per gallon (gpg). A gpg is
tener system) in softened water;
•
increased effectiveness of detergents and soaps;
Table 3: Hardness Classifications (Concentration of Hardness)
In Grains per Gallon
In Milligrams per Liter
(mg/L)
Relative Hardness Level
Below 3.5
Below 60
Soft
3.5 to 7.0
60 to 120
Moderately Hard
7.0 to 10.5
120 to 180
Hard
10.5 and above
180 and above
Very Hard
Health Contaminants
sources of the contaminant in public
to determine the quality of your
The parameters outlined in Table 4
water systems, these contaminants
water.
are some common contaminants
are regulated under the EPA Pri-
that have known health effects. The
mary Drinking Water Standards.
table lists acceptable limits, poten-
You may want to test for these con-
tial health effects, and possible
taminants in your private water well
17
Water Quality Standards and Interpretation
Table 4: Standards, Sources, and Potential Health Effects of Common Regulated Contaminants
Contaminant
Acceptable
Limit
Sources
Potential Health Affects at
High Concentration
Fecal Coliform
Bacteria
zero
Human sewage and animal
waste leaking into well or from
ground water contamination
Gastrointestinal distress, shock. Infants, elderly, individuals with a compromised immune
system and the sick are especially susceptible.
Fluoride (F)
4.0 mg/L
Fluoride is leached from natural deposits.
Mottling of teeth and brittle bones. If less
than 0.7 mg/L contact your doctor or dentist
for recommendations about the need for additional fluoride for small children and the elderly.
Selenium (Se)
0.05 mg/L
Selenium is leached from
natural deposits.
Dangerous to humans and animals alike.
Horses are especially susceptible exhibiting
hoof [nail] damage, hair loss, still born foals,
weight loss and with long term exposure,
death. Human and other animals share the
same symptoms.
Lead (Pb)
0.015 mg/L
Used in batteries; may be
leached from brass faucets,
lead caulking, lead pipes and
lead soldered joints. Is also
leached from natural deposits
Nervous disorders and mental impairment
especially in fetuses, infants, and young children. Also, kidney damage, blood disorders
and hypertension, low birth weights.
Arsenic (As)
0.05 mg/L
Arsenic is leached from natural deposits.
Dangerous to humans and animals alike. May
cause skin damage, circulatory system problems and an increased risk of cancer.
Nitrates and
Nitrites
10 mg/L as
nitrate-N
Byproduct of agricultural fertilization, human and animal
waste leaching to groundwater; also leached from natural
deposits.
Serious health threat for infants (birth to 6
months). Symptoms include shortness of
breath and blue-baby disease; lower health
threat to children and adults.
[1.0 mg/l as
nitrite-N]
Radon (Rn)
30 pCi/L
Naturally-occurring radioactive gas formed from uranium
decay; can seep into well water from surrounding rocks
and be released in the air as it
leaves the faucet.
Continued breathing of radon gas increases
chances of lung cancer; may increase risk of
stomach, colon, and bladder cancers.
Uranium (U)
0.03 mg/L
Uranium is leached from natural deposits
High levels suggest the presence of Radon
gas. Increased risk of cancer and kidney toxicity.
18
Water Quality Standards and Interpretation
Methane in Groundwater
Methane is a colorless, odorless and
tasteless gas, which is produced by
biological decay of organic materials
or by high temperatures and pressures acting on organic materials.
These materials include coals, organic rich shales, landfill materials,
compost piles and other accumulations of organic materials both
above and underground. Methane is
also produced in the digestive sys-
monitoring and treatment should be
level the more aggressive the
tem of humans and animals, and has
considered and implemented.
removal system must be.
no known direct health effect. The
Treatment for removing or lowering
specific source of methane found in
the concentration of methane in the
The system in Figure 1 is suitable for
groundwater in Colorado, can gen-
water delivered into a house is rela-
low-to-medium levels of methane,
erally be determined by detailed
tively simple and includes vented
whereas Figure 2 describes a sys-
and relatively expensive laboratory
wellhead caps, cisterns, some form
tem for higher levels of methane.
analysis.
of aeration and ventilation to allow
the methane to safely dissipate out-
Methane in water wells becomes a
doors rather than accumulate within
problem when it is allowed to build
your home, well house or other con-
up in confined spaces and become a
fined space. When you find meth-
potential safety hazard. These high
ane in your well water, additional
concentrations of methane can dis-
regular testing and monitoring
place oxygen, or in the presence of
should be performed since methane
a spark, can explode. Extensive
levels can fluctuate over time.
testing for methane in water wells in
Colorado has been conducted dur-
Figures 1 and 2 on page 20
ing the past twenty years. As a re-
demonstrate two types of methane
sult of this testing, many believe that
treatment, one a small cistern or
methane concentrations below 1
tank method and the other a more
mg/L are considered harmless.
detailed two chambered cistern.
Methane levels up to 7 mg/L usually
Details of operation are found with
are not a concern but should be
the figures. In addition, for lower
monitored for changes. Also, care
levels of methane, a vented well cap
should be taken to ventilate con-
may be a sufficient treatment. As a
fined spaces where well water is
general rule, the higher the methane
used. Above 7 mg/L additional
19
Water Quality Standards and Interpretation
trapped methane to escape into the
air. At the same time the aeration
pump is blowing filtered air into the
water further driving off any residual
dissolved methane. When the
pump refills the cistern (200 to 300
gallons) the air pump continues to
blow for an additional 10 to 30 min-
Figure 1: Small Cistern
utes to assure that all of the meth-
Small Cistern
Since methane is lighter than air it
ane is removed. The methane free
This small cistern system can be
will rise to the top of the cistern and
water moves into the passive (stor-
installed in a basement, garage, util-
vent. The gas must be vented out-
age) side of the cistern which is also
ity room or pump house. The active
side of any structure and never al-
vented. The methane must be
removal of methane is achieved by
lowed to accumulate inside. Re-
vented outside of any structure and
spraying the water into the open
member that this system should be
never allowed to accumulate inside.
space of the cistern / tank and al-
installed by a licensed pump installer
lowing the escaped gas to vent out.
or plumber.
Because of the complexity of systems like this they should be installed by a licensed pump installer
or plumber familiar with control systems.
Where Can I Get Additional
Information?
Further assistance with interpretation of your household water quality
test report is available. If you have
any problems understanding the
way the information is presented on
the report, you should contact the
testing laboratory directly for expla-
Figure 2: Large Cistern
nation. To assist you in evaluating
Large Cistern
are set about 12 inches above the
the significance of your results, and
This system is an aggressive system
bottom.
any actions you should take to solve
identified problems, or for further
and is usually installed outside and
When the water in the passive
information on contaminants not
ber one or two spray bars are in-
chamber is low enough the controls
discussed in this publication, you
stalled about 15 - 20 inches below
turn on the well pump and the air
may want to contact your local
the top. One or two aeration bars
pump (Jacuzzi type). The water
Health Department or environ-
sprays upward allowing much of the
mental professional. If you wish to
underground.
In the active cham-
20
Water Quality Standards and Interpretation
obtain more background informa-
rience in the treatment of your wa-
tion about the occurrence of con-
ter’s problems. Ask for references,
taminants and their effects on
certifications, training credentials
household water quality, particularly
and the names of others who have
as it pertains to established drinking
used their services. Check with the
water standards, call the EPA Safe
Better Business Bureau for con-
Drinking Water Hotline at (800)
sumer complaints. Ask how long
426-4791. Or you can explore sites
the professional has been perform-
on the internet starting with one or
ing his services. Don’t be shy. Ob-
more of the web sites listed in this
tain recommendations and quota-
booklet.
tions from more than one professional. Verify the terms of warranty
Where Can I Get Additional Help
claims on both equipment and in-
For Water Treatment?
stallation. Ask to see the technical
Sources for water treatment assis-
information on your proposed sys-
tance are usually found in most Yel-
tem before signing any contract.
low Pages under the headings of
“Water Purify & Filter Equipment” or
If you have any doubts about the
“Water Treatment Equipment, Serv-
contract drawn up by the profes-
ice and Supplies”. Additional assis-
sional, seek legal assistance before
tance can often be found by talking
signing. Look up web sites on the
to the local Health Department and
specific types of equipment that
in some cases the laboratory that
your professional recommends, talk
analyzed your water. Care should
to your friends, ask a lot of ques-
be taken when a professional offers
tions, and if you don’t get answers,
to test your water or demonstrates
don’t buy until your questions are
in-home water quality tests. Many
answered. If you can’t afford the
of these in-home tests are difficult
entire system ask for a recommen-
to perform and can provide mislead-
dation on a basic system to treat the
ing information. If possible use an
major problem(s) to start with, and
independent testing laboratory that
make sure that it will be compatible
is certified. A listing of certified
with any upgrades in the future.
laboratories can be found at:
http://www.cdphe.state.co.us/lr/pag
es/cert/SDWList.pdf .
As with the use of any technical
service, care should be taken to assure yourself that the professional
you have chosen has specific expe-
21
Remember that you are the
owner of a small domestic water treatment system; essentially a small version of the
public systems in cities and
towns.
Consequently, it will need to be
maintained on a regular basis.
Make sure that you are provided with the technical manuals for your system and ask
your professional to set up a
regular maintenance schedule
for you to follow, including
follow-up and annual visits by
your professional. Record all
system maintenance in the Basic Well Data section at the
end of this booklet.
Water Treatment Decision Guide
Is the TDS (total
Is the pH of your
Do bacteria keep
Are there bacteria
dissolved solids) of
water between 6.5
coming back after
in your well water
your well water
and 8.5?
disinfection of your
or does your water
NO
NO
YES above 500mg/L? NO
well?
smell bad?
Is the hardness of
your well water
above 180 mg/L?
NO
YES
YES
NO
YES
YES
Disinfect the well. Contact the Health Department or use a commercial disinfection kit. Always use care with dangerous chemicals.
Disinfect the well again
and wait a full 24 hours
before flushing the system. If the bacteria
problem continues install a disinfection system. These include
chlorination, ozone, and
the use of ultraviolet
(UV) light, to name a
few. It is best to have a
trained professional
install and train you how
to use the system.
pH adjustment of the
well will require the services of a trained professional.
May require the installation of a reverse osmosis
unit, if the taste of the
water is a problem.
May require softening of
the hot water side of
your system.
ALSO
ALSO
A test for lead and copper is suggested if the
pH is below 6.5
If the hardness is above
120 the water may have
to be pre-softened. Soft
water should be only for
the RO unit and the hot
water system. Soft water can harm plants and
lawns. It is corrosive to
uncoated copper and
galvanized pipe so inspect your system on a
regular basis.
ALSO
The well may require
testing more often. Try
to find the contamination source. Check the
well seal, water piping
system and hot water
heater. Have a professional check for surface
water contamination.
Shallow wells may need
additional treatment
technologies.
ALSO
See page 24 for procedure for disinfecting
your well.
ALSO
Other types of bacteria
may be present as slime
bacteria, sulfate reducing bacteria, etc. that are
difficult to remove with
a single disinfecting of
your well.
ALSO
ALSO
A test for zinc is suggested if the pH is below
6.5 and you have galvanized piping.
The well may require
testing more often. Try
to find the contamination source. Check the
well seal, water piping
system and hot water
heater. Have a professional check for surface
water contamination.
Shallow wells may need
additional treatment
technologies.
Note
Pregnant women and
children under the age
of 6 months can be
harmed by drinking
water with nitrite levels
above 1.0 mg/L. If in
doubt about the effectiveness of your treatment system drink bottled water until testing
confirms reduction of
nitrite-N to below 0.1
mg/L.
ALSO
22
Above 200 mg/L?
YES
Treated water may have
a salty taste.
Above 300 mg/L?
YES
Seek the advice of an
experience environmental professional, a
licensed and experienced pump installer or
contact the local Health
Department for additional assistance.
ALSO
May require RO treatment to remove a salty
taste if the water has
been softened.
Is the nitrite-N or
total nitrate/nitriteN in your well 1.0
NO
mg/L or above?
YES
Lower than 10 mg/L?
YES
The well may require
testing more often. Try
to find the contamination source. Check the
well seal, water piping
system and hot water
heater. Have a professional check for surface
water contamination.
Shallow wells may need
additional treatment
technologies.
ALSO
If the total nitrate/nitriteN is 1.0 mg/L or higher
and there are children
below 6 months of age
or pregnant women,
stop drinking the water
and contact the health
department.
ALSO
Test for nitrite-N and if
the total is 1.0 mg/l or
above do not drink the
water without treatment. See note to the
left.
Is the iron in your
well water above
0.3 mg/L?
Is there a rotten
egg smell in your
well water or does
NO
it contain
methane gas?
YES
Does the water turn red
or black after standing
NO in a glass?
YES
NO
YES
Does the water smell like
rotten eggs?
NO
Between 2.0 mg/L and
4.0 mg/L?
YES
YES
You can smell rotten
egg gas (hydrogen sulfide) at a lower concentration than a laboratory
can analyze. However, a
little and a lot both smell
the same. If you have
hydrogen sulfide in your
well and your home has
a thick sweet odor that
is unrecognizable, be
careful. This is a sign
that the level of hydrogen sulfide can be
deadly. Call the Health
Department or the local
fire district.
May require the installation of a reverse osmosis
(RO) unit, if the taste of
the water is a problem
or directed by your
health care provider.
YES
Seek the assistance of
an experienced environmental professional,
a licensed and experienced pump installer or
contact the local Health
Department for additional assistance.
May require any one of
several types of iron
filters. These systems
include a simple water
softener (for Iron below
1-3 mg/L), green sand
type filters, backwashable filters, etc.
ALSO
Seek the assistance of
an experienced environmental professional,
a licensed and experienced pump installer or
contact the local Health
Department for additional assistance.
Does the well contain
methane gas?
ALSO
If the hardness is above
120 the water have to be
pre-softened. Soft water should only be for
the RO unit and the hot
water system. Soft water can harm plants and
lawns. Also soft water is
corrosive to uncoated
copper and galvanized
pipe so inspect your
system on a regular
basis.
Above 4.0 mg/L?
YES
Stop drinking the water.
Call the local Health
Department.
ALSO
Above 10 mg/L?
YES
YES
Below 1 mg/L there is
usually not concern. Up
to 7 mg/L you may
want to test for value
changes. Above 7 mg/L
monitor the well regularly and implement
methane mitigation
measures. See pages 19
& 20 for treatment options.
Seek the assistance of
an experienced environmental professional,
a licensed and experienced plumber or pump
installer for assistance in
choosing a treatment
method such as RO,
softening, or direct ion
exchange.
NO
Is the fluoride in
your well water
higher than
2.0 mg/L?
23
Seek the assistance of
an experienced environmental professional,
a licensed and experienced pump installer or
contact the local Health
Department for additional assistance.
Is the selenium
value above 0.05
mg/L or are any
NO
trace metals in
your water greater
than the EPA
Guidelines?
YES
Selenium above or near
0.05 mg/L must be
NO treated before it can be
used for drinking water
for humans and animals.
Selenium values may
vary during the year.
ALSO
If uranium is above 0.03
a test for radon gas is
suggested.
ALSO
Seek the assistance of
an experienced environmental professional,
a licensed and experienced pump installer or
contact the local Health
Department for additional assistance.
Chlorination Techniques
When to treat your well with
water well contractor, pump installer
How to determine the amount of
chlorine?
or licensed plumber. If you have
Chlorine bleach to add to your well.
You should disinfect your well if your
water treatment devices, consult
Use basic 5 % to 6% household
test for bacteria is positive, or fol-
with your water treatment company
laundry bleach (Sodium Hypochlo-
lowing any construction, installation,
before beginning the chlorination
rite). DO NOT USE any of the newer
maintenance, or repair of your well
process. Always use rubber gloves
concentrated products, dry bleach
and other water systems. Disinfect-
as well as a splash apron and eye
or any of the “Fresh Scent,” “Lemon
ing is essential if there has been
protection when handling bleach.
Scent” or similar forms of bleach.
flooding or other obvious signs of
Avoid contact with the bleach. If
The cheapest or generic brand is
contamination in or around or in
you should splash this solution on
usually free of added materials.
your well. The disinfecting process
your person or clothing, immedi-
most often recommended is “shock
ately rinse thoroughly with water.
Three pints of bleach should be
chlorination”. Shock chlorination is
added for every 100 gallons of
the process by which wells are sani-
standing water in the well. To de-
tized using household chlorine
termine the amount of standing wa-
bleach and is effective in home wa-
ter in your well you need three
ter systems such as wells, spring
measurements (see Figure 3 to the
houses, and cisterns. Routine shock
left):
chlorination is NOT recommended
1.
The diameter of your well which
for treating recurring bacteria prob-
can be found in your drill log or
lems. For these continuing chronic
from a measurement that your
bacteria problems contact a reputa-
driller or pump installer can
provide.
ble licensed water treatment expert
2. The total depth of your well (a),
who is familiar with your area.
which you can obtain from your
What precautions should I take
well’s drill log or from a meas-
prior to chlorination?
urement provided by your driller
Make sure that everyone in your
or pump installer.
3. The depth from the top of your
home is warned not to use the water during the treatment process.
well to the top of the water (b).
Arrange for an alternative source of
This measurement can also be
drinking water. Special care should
provided by your driller or
be taken to ensure that children and
pump installer.
older adults do not consume tap
The depth of water in your well is
water during the treatment process.
Unless you are familiar with water
wells, and are comfortable working
calculated by subtracting measureFigure 3: Well Capacity Calculation
ment b from measurement a, which
equals c (depth of water).
with chemicals, the well chlorination
should be performed by a licensed
24
Chlorination Techniques
From the chart below determine
pints of household bleach. You will
bacterial contamination found in
how much standing water is in your
also need to add an extra three (3)
your well. Inspect all areas and
well. Generally, there are two types
pints to treat the household plumb-
surfaces that may be a source
of wells, drilled and bored. The in-
ing such as the pressure tank, hot
of dust or other contamination
side diameter of the casing (well
water heater, and pipes. So for this
in and around the system. After
pipe) of a drilled well is typically
example you will use a total of
every possible contamination
from 4 to 8 inches. Bored wells are
twelve (12) pints or 1.5 gallons of
source has been eliminated, the
larger, ranging from 24 to 36 inches.
household bleach.
water supply should be disin-
Refer to the following table to de-
fected as outlined below:
termine your well’s storage per foot
Basic Chlorination Technique
of water. If you use a cistern, tank
The following basic technique has
apron and eye protection, dilute
storage or have a hand dug well you
been recommended by many Health
the amount of bleach you de-
will need to contact your local
Departments and other agencies.
termined (see procedure above)
health department or pump installer
Many web sites have additional or
to be adequate for your well’s
for additional information and assis-
more detailed instructions for the
water volume by first adding 2
tance to disinfect your system.
disinfection of domestic drinking
to 3 gallons of water in a 5 gal-
water wells that have been deter-
2. Wearing rubber gloves, a splash
lon bucket and mixing carefully.
3. Remove the well seal at the top
Table 5: Water storage per foot in various size boreholes.
of the well. Now carefully pour
Bored Well
Drilled Well Pipe
the bleach mixture into your
Diameter
(inches)
Storage per Foot
of Water (gal/ft)
Diameter
(inches)
Storage per Foot
of Water (gal/ft)
well using a large funnel. Wait
4"
0.653
24"
23.5
additional 15 or 20 gallons of
6"
1.47
36"
52.9
fresh water from a nearby hose
8"
2.61
about 15 minutes and run an
bib into the funnel to treat the
well bore sides.
4. Now open a cold water faucet
Example: A drilled well with a 6”
mined to have bacterial contamina-
diameter has a storage per foot of
tion. There are three listed at the
in the system and run the water
water capacity of 1.47 gal/ft. Next
end of this section. If you use a
until you can smell the chlorine
multiply your total depth of water
commercially available disinfection
bleach odor. Turn off the faucet.
“c” times your storage per foot of
kit follow the manufacturer’s direc-
Now do the same for ALL cold
water “s.' For example if we will as-
tions.
water faucets on the system.
sume that “c” is 204 ft. The volume
1.
Before disinfection, inspect your
Also flush the toilets. Turn off
of water in your well is: 204 feet x
water system (or have it in-
your hot water heater and run
1.47 gal/ft = 300 gal. To disinfect
spected by a professional) to
hot water until you smell chlo-
your system (well and piping to and
determine and correct any
rine. Now repeat for all hot wa-
in your home) add 3 pints of bleach
damage, faults or design prob-
ter faucets, to allow the piping
into your well for every 100 gallons
lems that may exist. These
and the heater to be treated.
of water, or in this case nine (9)
problems may contribute to the
25
Chlorination Techniques
5. Allow the bleach to remain in
system, streams, rivers, ponds
Helpful web sites:
the entire system for 24 hours
or lakes as the chlorine bleach
Boulder County web site
(at least overnight). During this
may disrupt the operation of
http://www.waterwell.cc/CHLORIN.H
wait period do not use the wa-
the septic system or kill wildlife.
TM
ter for any purpose. This is to
6. Wells with excessive bacterial
allow the disinfectant to kill all
contamination or wells that con-
University of Georgia web site
the bacteria within the system.
tain slime, iron or sulfate reduc-
www.fcs.uga.edu/pubs/PDF/HACE-
After the overnight or 24 hour
ing bacteria may require more
858-4.pdf
wait, flush out the remaining
than one treatment or the in-
chlorine by turning on outside
stallation of a permanent disin-
Lake County Illinois web site
faucets letting them run until
fection system.
http://www.lakecountyil.gov/Health/
the chlorine smell dissipates.
7. Two days after the system is
Finally, run the indoor faucets
flushed obtain a sterile sample
until the smell of chlorine is
bottle from your local Health
gone. Minimize the amount of
Department or a certified labo-
the water going into your septic
ratory and test for bacteria to
assure that your treatment was
effective. Take this sample as
directed from a clean water tap
that does not have an aeration
head (a possible source of contamination) and take it back to
the Health Department or laboratory as soon as possible
(within 6 hours).
If your well does not respond to two
or three treatments, as described
above, contact a licensed pump installer, a water treatment specialist
or a licensed plumber familiar with
water treatment systems.
26
want/Documents/WellChlorination.
pdf
Trouble Shooting Guide
Q – Why does water not come from
Q – Why does my pump seem to
my well anymore?
run every time I turn on the tap?
A – There may be several reasons
A – The pressure in your water sys-
why water is not delivered from a
tem is regulated by a pressure tank
well. First check your breaker box
so that the pump does not have to
Q – Why does my water smell like
to see if the breaker is tripped. You
be run every time there is demand
sulfur or have sewer like smell.
should call a licensed pump installer
for water. The tank has an air blad-
A – Your well probably has bacteria
to check the pump and pump con-
der in it that can rupture. Have a
in it. Have the water tested for bac-
trol equipment, which may have
licensed pump installer or plumber
teria immediately. The local Health
failed. The pump installer can also
check the pressure tank and the
Department or a licensed pump
check the water level in the well.
pump control unit.
installer can help disinfect the well
Overuse of the aquifer may have
and find the source of the bacteria.
dropped the static groundwater
Q – Why does my water leave
level below the depth of your well or
stains on fixtures and clothes?
Q – Why does my water smell or
pump. The pump may have to be
A – Your water likely has lots of dis-
taste like chemicals?
reset at a lower level or the well re-
solved minerals in it. Have the water
A – Your well may be polluted with
placed with a deeper well.
tested by a laboratory to determine
chemicals. Stop using the water
its chemical composition. You can
immediately. Call the Health De-
Q – Why does my well seem to
then use the Water Treatment Deci-
partment to help you find out where
pump less water than it used to?
sion Guide in this booklet, or call a
the source of the chemical contami-
A – Over time minerals or bacteria
licensed pump installer to help you
nation may be and what to analyze
can constrict your water well screen
decide what treatment equipment
your water for. Have the water
or your water system pump or pip-
may be appropriate for your well
tested by a laboratory for likely
ing. Overuse or seasonal lack of
and water.
chemical pollutants.
cause the static groundwater level
Q – Why is there a lot of sediment
Q – Why does my water fizz?
to drop and thus decrease the
in my water?
A – Your well water has gas dis-
amount of water that can enter the
A – Your well may have been im-
solved in it. This gas may be harm-
well. A licensed well driller or pump
properly developed to remove ex-
less air or carbon dioxide. It may
installer can clean your well screen
cess drilling fluids and sediment
also be methane or radon. Have the
and check your pump, piping and
when it was drilled. Or your well
water tested by a laboratory to de-
water level. They can also measure
casing or well seals may have failed.
termine what the gas is and whether
the yield of your well and compare it
Your cistern (if you have one) may
or not a treatment system is neces-
to the yield when the well was
also need cleaning or is damaged.
sary. A licensed pump installer can
drilled. Keep good records of all of
Have a licensed well driller or pump
find air leaks in the water system if
these checks and maintenance ac-
installer inspect the system and de-
that is the indicated problem. The
tivities as they can be used in the
termine the source of the sediment.
pump installer can also help with the
recharge of the aquifer can also
appropriate treatment system.
future to help diagnose problems.
Record these in the Data section at
the end of this booklet.
27
Water Testing Glossary
Acidic – descriptive term used in
CDPHE – Colorado Department of
are usually seen on your report as:
reference to water having a pH of
Public Health and Environment is
TNTC (too numerous to count) and
less than 7; pertains to the corro-
responsible for the enforcement of
confluent growth. You may need to
siveness of water.
EPA public drinking water regula-
call your licensed pump installer or a
tions within the State of Colorado.
water treatment professional to as-
Acute Health Effects (acute toxic-
CDPHE works with EPA, local health
sist in treating chronic bacteria
ity) – Any poisonous effect with a
departments and when needed with
problems.
sudden and/or severe onset pro-
sovereign Indian Tribes, who often
duced within a short period of time
have their own environmental de-
Concentration – The amount of a
after using contaminated water, re-
partments. See the web site list at
given substance (weight) in a spe-
sulting in mild to severe biological
the end of this booklet for a link to
cific amount of water (volume) and
harm or illness. Acute symptoms
CDPHE.
is often expressed as mg/L or ppm.
stomach, loose stool, bowel upset,
Chronic Health Effects – Chronic
Contaminants – Naturally occurring
and gastrointestinal difficulties. If
means long-term. Chronic health
substances when present in high
symptoms occur as a result of drink-
effects occur and persist as a result
enough levels make water unfit for
ing contaminated water, medical
of repeated or long term use of con-
drinking and/or other household
attention should be sought
taminated water. Often, it takes
uses. Some contaminants are man-
promptly.
many months or years of exposure
made or come from human activi-
for chronic health effects to occur.
ties such as farming, mining, live-
Aesthetic Characteristics – The
Chronic health effects include irre-
stock, etc.
non-health related characteristics of
versible damage to internal organs,
water that make it desirable for hu-
and changes to our gene structure,
man use. Generally taste, color,
which can result in cancer, birth de-
odor, and turbidity are considered to
fects, disabilities, and additional
be aesthetic characteristics.
problems.
include, but are not limited to, upset
Coliform Bacteria – A type of bac-
pH greater than 7 is alkaline (non-
teria that is found in the intestinal
acidic).
tract of all animals, including hu-
laboratory certified by the CDPHE
as qualified to test drinking water.
Information about local stateapproved laboratories is available at
the Health Department. See the
web site list at the end of this booklet for a list of certified labs.
acidic or "soft" may be corrosive
and may deteriorate plumbing and
leach toxic metals such as lead, zinc
and copper from pipes.
Alkaline – A water sample having a
Certified Testing Laboratory – A
Corrosive Water – Water that is
mans. These bacteria are used as an
indicator of well cleanliness. If the
coliform test is unacceptable, it is an
indicator that your well is polluted
and that additional tests or treatments are advisable. If the disinfection of your well does not remove
Corrosivity Index – One of the
methods for assessing the scale dissolving (corrosive) or scale forming
potential of water. A positive number indicates a tendency to deposit
calcium and magnesium carbonates.
If the result is negative, it is an indication that the water will dissolve
carbonates and enhance corrosion.
the coliform bacteria seek the assis-
Detection Limit – The minimum
tance of your local Health Depart-
concentration of a substance that
ment. Unacceptable coliform tests
may be measured in the laboratory
28
Water Testing Glossary
and reported in the given testing
"soft"; while hard water above 7
standing body of water and have an
method. Many laboratory reports
grains per gallon (120 mg/l) may
iridescent sheen that is often mis-
will state what the detection limit is
affect the appearance of plumbing
taken for an oil spill.
for each contaminant.
fixtures, the lifespan of water heaters, and the efficiency of detergents.
Disinfection – The destruction of all
Maximum Contaminant Level
(MCL) – The maximum level of a
pathogenic organisms, with chlorine,
Health Risk – The risk or likelihood
contaminant which is permitted in
ozone, ultraviolet light or heating.
that a chemical will adversely affect
public water supplies. Maximum
a person's health. Estimating health
contaminant levels are specified in
EPA – The abbreviation for the Envi-
risks of various chemicals is a com-
the Primary Drinking Water Stan-
ronmental Protection Agency, prop-
plex and inexact science.
dards set by EPA and the CDPHE
erly called, "the United States Envi-
for contaminants that affect the
ronmental Protection Agency". This
Heavy Metals – Elements with
agency has the responsibility of de-
higher molecular weights, which are
veloping and enforcing Primary
generally toxic in low concentrations
Methane – A colorless, odorless,
Drinking Water Standards for public
to plant and animal life. Examples
flammable, lighter-than-air gas that
drinking water systems. EPA does
include mercury, chromium, cad-
can be found in water wells which
not regulate private wells or cisterns.
mium, arsenic, selenium, and lead.
are completed in coal seams, or
The EPA also develops, but does not
safety of public drinking water.
other zones that contain trapped
enforce, Secondary Drinking Water
Hydrogen Sulfide – A hazardous,
gasses. Although methane is not a
Standards. See the web site list at
poison gas that smells like rotten
poison, if it is allowed to accumulate
the end of this booklet for a link to
eggs. It is sometimes produced by
in confined spaces it can pose a risk
EPA.
bacteria in well waters. It can be
for explosion or fire. Methane is eas-
found in local water wells at concen-
ily removed by proper venting.
Grains per Gallon (gpg) – Apothe-
trations that are a nuisance but are
caries' weight of a chemical sub-
not poisonous. However in high
Milligrams per Liter (mg/L) – Metric
stance in one gallon of water used in
concentrations the gas can accumu-
weight of a substance in a liter of
the water-conditioning trade to in-
late in low areas and become toxic
water. 1 mg/ L = 1 ounce per 7,500
dicate hardness of water. One gpg
and/or explosive. Use caution when
gallons. (1 mg/L = approximately 1
equals approximately 17 mg/L of
you smell hydrogen sulfide.
ppm in water)
Iron Bacteria – Microorganisms that
Nitrate/nitrite-N – A salt form of the
Hardness – A water quality problem
feed on iron in the water. They may
element nitrogen. The presence of
in many areas in Colorado. Hard-
appear as a slimy rust-colored coat-
nitrates and/or nitrites in a water
ness is a relative term. It describes
ing on the interior surface of a toilet
supply generally indicates pollution
the content of the dissolved miner-
flush tank or as a dark colored glob
by human or animal waste, and/or
als, calcium and magnesium, and is
of gelatinous material or sand-like
commercial fertilizer. These materi-
reported as grains per gallon or mg/
lumps of black sediment in the wa-
als are very dangerous for children
l. Water with less than 3.5 grains per
ter. Iron bacteria colonies will some-
below the age of six months.
gallon (60 mg/l) is considered
times float on the surface of a
hardness.
29
Water Testing Glossary
Nuisance Contaminants – Contami-
alkaline has a pH greater than 7. The
Public Water System – In Colorado,
nants that affect aesthetic or func-
secondary standard for drinking
a public water system is one that
tional aspects of water quality and
water is a pH between 6.5 and 8.5.
serves at least 15 connections (for
have little or no impact on health.
example households) or at least 25
They are managed in public drinking
Pollutants – Man-made substances
individuals. CDPHE and EPA regula-
water systems as Secondary Maxi-
introduced to the environment that
tions apply to public water systems.
mum Contaminant Level (MCL)
at high enough levels can make wa-
Standards.
ter unfit for human, animal, or plant
Pure – Without contaminants or
consumption or use.
pollutants.
cals that contain carbon. If not
Potable Water – Water that is fit for
Radon – A tasteless, odorless, color-
properly handled, stored, trans-
drinking.
less radioactive gas formed from
Organic Chemicals – Those chemi-
ported, and disposed, organic
decay of uranium in rocks. Radon
Primary Drinking Water Standards
has been found dissolved in some
– The Primary Drinking Water Stan-
groundwater supplies. Activities
dards for public water supplies are
that release radon as vapor from
published by the EPA and moni-
water include showering, bathing,
tored, and enforced the CDPHE.
and cooking. High concentrations
Primary standards regulate con-
of radon are known to be carcino-
taminants which pose serious health
genic and are linked with increased
risks to the water user. The primary
risk of lung and other cancers. Ra-
standards are only enforceable in
don is easily removed from water by
Parts per Million (ppm) – Concen-
public water systems and should be
purging with air and venting
tration of a substance on a weight
used as a guide for your personal
basis in water. 1 ppm = 1 pound of a
drinking water well. For a link to
Safe – The level of a contaminant or
contaminant per million pounds of
these standards see the web site list
pollutant is low enough that no
water (1 ppm in water = approxi-
in this booklet for a link to CDPHE
health problems will occur.
mately 1 mg/L)
or the EPA.
Pathogens – Live organisms that
Private Water Systems – Any sys-
up on the inside of water pipes and
contaminate water. Examples in-
tems which do not meet the defini-
water-using appliances, like coffee
clude bacteria, viruses, and parasites
tion of public water systems, for
pots and water heaters. It is made
such as Giardia.
example, a private individual water
of calcium and magnesium carbon-
source, such as a residential water
ates and usually associated with
pH – A factor used to measure the
well. Private water systems are not
hard water. Small amounts of scale
acidity and alkalinity of water. Val-
regulated by local health depart-
are helpful in preventing leaching of
ues for pH fall on a scale ranging
ments, the CDPHE or the EPA.
metal from pipes.
chemicals can pollute water supplies. These can include trihalomethanes, pesticides, volatile organic compounds such as benzene,
toluene, ethylbenzene, and xylenes
(constituents of crude oil, condensate, and gasoline) and in some areas pharmaceuticals.
Scale – Mineral deposits which build
from 0 to 14. Water that has a pH of
7 is neutral; water that is acid has a
pH lower than 7 and water that is
30
Water Testing Glossary
Secondary Drinking Water Stan-
Toxic Metals – Arsenic, barium,
chemicals, including the solvents
dards – The Secondary Drinking
chromium, mercury, selenium, lead,
such as trichloroethylene and car-
Water Standards are published by
and other toxic metals are regulated
bon tetrachloride, and the gasoline
the EPA. Secondary Standards set
by EPA Primary Drinking Water
component, benzene. Tests for VOC
desirable/acceptable levels for nui-
Standards. Toxic metals may be
compounds are not routine and
sance contaminants, which affect
naturally occurring in rock and soil,
tend to be fairly expensive because
taste, odor, color, and other aes-
or may pollute water as a result of
of the difficult and precise labora-
thetic and functional qualities of the
runoff or leaching from industrial or
tory work involved. Low levels of
water supply. These secondary
agricultural sites, mining activities or
VOC’s can be treated with activated
standards are not enforced by law,
hazardous waste disposal.
charcoal filter systems. Treated wa-
but rather are guidelines for public
ter must be tested to assure that the
water treatment plants and state
Toxicity – The toxicity (poisonous
treatment has reduced the VOC’s to
governments. These guidelines are
effect) of a water contaminant de-
a safe level before using as drinking
helpful as you read the laboratory
pends on the concentration of the
water. Filters must be replaced of-
results from your well. For a link to
contaminant in the water and the
ten.
these standards see the web site list
period of time the contaminated
in this booklet for a link to CDPHE
water is consumed. Any chemical
Water Quality – In general is deter-
or the EPA.
can be toxic, if you swallow enough
mined by these characteristics:
of it. Also, people react differently
safety, taste, color, smell, corrosivity,
Total Dissolved Solids (TDS) – A
to different toxic substances; some
staining, pH, hardness, and chemical
good general indicator of water
people may be harmed more than
composition of dissolved solids.
quality, which measures the total
others. Pregnant and nursing
amount of dissolved minerals, met-
women, the elderly, infants, ill or
als, and salts. Water with more than
malnourished people, and people
500 milligrams per liter TDS is of
taking medication or that have a
marginal quality and may contain
compromised immune system may
undesirable amounts of calcium,
be especially vulnerable to certain
magnesium, sulfates, chlorides, or
contaminants.
other salts for human consumption.
Many wells produce water that has
Turbidity – A cloudy condition in
much higher levels of TDS and in
water due to suspended clay or or-
many areas may be the only source
ganic matter. Turbidity can be
of water. High levels of TDS are of-
treated with filters.
ten safe to drink, but may cause
transient gastric problems. These
higher levels of TDS can be removed, but often at a higher cost
than routine water treatment..
Volatile Organic Chemicals
(VOCs) – Hydrocarbon containing
compounds which evaporate readily
and are expensive to analyze. Primary Drinking Water Standards set
limits for several volatile organic
31
Text and glossary are freely adapted from
publications provided by various state and
local agencies and the Colorado Department
of Public Health & Environment.
Record of Basic Well Data
Use this form to help document the history of your well.
General Information
Owner's Name:
Owner's Address:
Permit #:
Well Location:
Driller Name:
Phone #:
Pump Installer Name:
Phone #:
Date Drilled:
Pump Installation Date:
Installation Data
Well Depth:
Surface Casing Depth:
Production Casing Diameter:
Cement Interval:
Well Screen Interval:
Pump Size & Type:
Pump Depth:
Water Levels
Yield Rates
Initial Static Water Level (feet bgs):
Initial Yield Rate (gpm):
Subsequent Static Water Levels
Subsequent Yield Rate
feet bgs:
Date:
gpm
Date
feet bgs:
Date:
gpm
Date
feet bgs:
Date:
gpm
Date
feet bgs:
Date:
gpm
Date
feet bgs:
Date:
gpm
Date
feet bgs:
Date:
gpm
Date
Well Maintenance – Record dates and descriptions of work performed.
Additional Notes:
32
Helpful Water Web Sites
US Environmental Protection Agency
http://www.epa.gov
http://water.epa.gov/drink/
http://water.epa.gov/lawsregs/rulesregs/sdwa/currentregulations.cfm
http://water.epa.gov/learn/kids/drinkingwater/index.cfm (stuff for kids to do)
http://water.epa.gov/drink/info/well/index.cfm
Radon
http://www.epa.gov/radon/
US Geological Survey
http://www.usgs.gov/water/
http://water.usgs.gov/ogw/
Colorado Department of Public Health & Environment
http://www.cdphe.state.co.us/
http://www.cdphe.state.co.us/wq/drinkingwater/PrivateWellInformation.html
Colorado Division of Water Resources
http://water.state.co.us/Home/Pages/default.aspx
http://water.state.co.us/groundwater/Pages/default.aspx
http://water.state.co.us/groundwater/wellpermit/Pages/default.aspx
http://www.dwr.state.co.us/WellPermitSearch/default.aspx
http://water.state.co.us/DWRIPub/Documents/constructionrules05.pdf
Colorado Oil & Gas Conservation Commission
http://cogcc.state.co.us/
Colorado State University Extension Service - Water Related Resources
http://www.ext.colostate.edu/pubs/water/water_related.html
The Groundwater Foundation
http://www.groundwater.org/gi/gi.html
National Groundwater Association
http://www.ngwa.org/Fundamentals/Pages/default.aspx
http://www.wellowner2.org/2009/
Water Quality Association
http://www.wqa.org/landing.cfm?section=3