Take Home Messages and Recommendations

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Rockingham County
Drinking Water Clinic
Interpretation Meeting
Cristin Sprenger and Amber Vallotton
Virginia Cooperative Extension
Erin Ling and Brian Benham
Virginia Tech Biological Systems Engineering, Virginia Cooperative Extension
Private Water Supplies in Virginia

1.7 million Virginians rely on wells, springs or
cisterns (22% of the population)

In the U.S. municipal water supplies are regulated by
the EPA under the Safe Drinking Water Act; private
supplies are not!

Homeowners relying on private water supplies:
◦ Are responsible for all aspects of water system management
◦ May lack knowledge and resources to effectively manage
◦ Usually don’t worry about maintenance until problems arise

Groundwater is a shared resource – our actions can
affect others’ water supplies too!
2
How does water move to my well?
(Bedrock/drilled well)

In a bedrock well, groundwater moves
through fractures, or cracks in the
bedrock

Water can come from many different
directions, depths, and sources into
one well

It can take water hours, days, or years
to move through to bedrock

Well casing extends through loose
“overburden” and into the bedrock,
where an “open” borehole continues
underground

Water can come from any fractures
that intersect the open borehole
3

At least 50-100’ and upslope from contamination sources

Not in an area that receives runoff

Ground slopes away from well

Well casing at least 12” above ground

Grout seal around casing (have checked by a well driller)

Sanitary well cap (drilled well) or sealed concrete cover
(bored well)
12”
12”
4
Photo credits: SAIF Water Wells ; Penn State University
Proper well location and construction
The Finished Product – Drilled Well
Sealed, sanitary well cap
Casing extending >12”
above ground surface
Ground sloping away
from casing
Grout seal
5
http://www.omafra.gov.on.ca/english/environment/06-117.htm
Well Maintenance Tips

Do not use fertilizers, pesticides, oil, or paint near well

Keep area around well clean and accessible

Keep careful records
◦ original contract, water test results and any
maintenance or repair information

Every year:
◦ Conduct thorough visual inspection of well
◦ Check cap for cracks, wear and tear, tightness

Every 1-3 years have well inspected by a qualified
professional (with WWSP classification)
6
Private Water Supply Regulations
• Virginia Private Well Regulations
o Specify application, inspection and
construction requirements
o No requirements for maintenance or water
testing after construction of well –
responsibility of the owner!
• EPA National Drinking
Water Standards
o Apply to PUBLIC systems
o Primary (health) and Secondary (nuisance)
o Can be used as guidance for private
systems to know “how much is too much”
7
EPA Drinking Water Standards
Primary Standards
Secondary Standards
• Also called Maximum
Contaminant Level (MCL)

Also called SMCL or RMCL

Cause aesthetic problems:
• Cause health problems
o
Staining
• Enforced for public systems
o
Taste
• Over 80 contaminants
o
Odor
• For example:

Can naturally occur in ground
water

About 15, including:
o
Nitrate
o
Lead
o
Coliform
o
Iron
o
Most organic chemicals and
pesticides
o
Sulfate
o
Manganese
8
Testing water quality

Why test?
◦ Protect family’s health and safety
◦ Many contaminants undetectable by human senses
◦ Preventive measures often more effective and less expensive
◦ Legal protection

When to test?
◦ Routine tests every 1-3 years
◦ Pregnant woman or infant in the home
◦ Recurring gastrointestinal illness
◦ Change in taste, appearance, odor of water
◦ Any services or repairs are done
9
What should I test for?

Every year test for coliform bacteria
◦ Simple, relatively inexpensive test
◦ Indicates possible contamination from human or animal waste

Every three years test:
◦ pH (secondary std: 6.5 – 8.5)
◦ Total Dissolved Solids (TDS; secondary std 500 mg/L)
◦ Other contaminants based on local land uses nearby and
condition of water
10
Understanding test results

Most results provided as concentrations:
◦ mg/L (milligrams per liter) ≈ ppm (parts per million)
◦ µg/L = (micrograms per liter) ≈ ppb (parts per billion)

Other units unique to test
◦ Hardness, pH

Compare to EPA standards:
http://www.epa.gov/safewater/contaminants/index.html
How much?
4 drops of ink in a
55 gallon barrel of
water results in an
“ink concentration”
of 1 mg/L or ppm!
11
Household water quality is complex!
Hydrogeology
Well location
Well construction
Well maintenance
Water Treatment
Plumbing
Local land uses
Surface activities
Photo credits: Penn State Univ., http://www.banthebagspdx.com/?p=283, USGS; http://www.clker.com/clipart-puzzle-pieces-2.html;
12
http://levahnbros.wordpress.com/2009/12/01/copper-pipe-leak/; http://www.pubs.ext.vt.edu/442/442-670/442-670.html
Sources of potential contaminants or
issues of concern
well
Surface water contamination: nitrate, bacteria
Where a contaminant
comes from affects how
we can deal with it!
Some are found in groundwater naturally,
either due to human activities on or below
ground:
Source may be plumbing
materials or existing water
treatment device:
sodium
copper
lead
bacteria
arsenic
TDS
iron
hardness
13
Options for problem water
1. If possible, control the source of pollution
◦ Divert runoff, maintain septic system
2. Improve maintenance of water system
◦ Install sanitary well cap, slope the ground
3. Treat the water to reduce contaminant concentration
◦ Match the treatment option to the pollutant
◦ Consult a professional
4. Develop a new source of water
◦ Deeper well, develop spring, connect to
water
public
14
http://static.howstuffworks.com/gif/septic-tank-cleaning-1.jpg, http://www.shipewelldrilling.com/Pictures/well_drilling_rig.jpg, http://www.clearflow.ca/REVERSE_OSMOSIS2.jpg
Treatment Considerations

Be sure to explore ALL of your options

Always have water tested by a certified lab

Look for National Sanitation Foundation (NSF) and
Water Quality Association (WQA) certifications,
consult Better Business Bureau (BBB)

Point of Use (POU) vs. Point of Entry (POE)

If it sounds too good to be true, it is! E.g., magnets

Weigh benefits and limitations of a device:
◦ Cost
◦ Maintenance requirements
◦ Warranty
15
Rockingham Questionnaire Results (n=81)
Problems experienced with water
% reporting
Staining of fixtures, appliances, laundry
32.1
Presence of particles
13.6
Objectionable odor
8.6
Unpleasant taste
4.9
Unnatural color or appearance
7.4
Corrosion of pipes and plumbing fixtures
4.9
Sources of potential contamination
% reporting
Stream (< 100’)
6.2
Septic (< 100’)
4.9
Oil Tank (<100’)
4.9
Field crop operation (< 1/2 mile)
64.2
Major farm animal operation (< 1/2 mile)
67.9
16
SAMPLE Test Report
Test
Iron (mg/L)
Manganese (mg/L)
Hardness (mg/L)
Sulfate (mg/L)
Fluoride (mg/L
Total Dissolved Solids
(mg/L)
pH
Sodium (mg/L)
Nitrate-N (mg/L)
Total Coliform Bacteria
E. Coli Bacteria
First Draw Data:
Arsenic (mg/L)
Copper (mg/L)
Lead (mg/L)
Flush Data:
Arsenic (mg/L)
Copper (mg/L)
Lead (mg/L)
Household Water
Sample
Maximum Recommended
Level or Range
ND
0.073**
44.7
1.2
ND
0.3
0.05
180
250
2
84.5
5.8**
8.1
ND
Present**
Absent
ND
1.1**
0.007
ND
ND
ND
** = exceeds
recommended
level
ND = not
detected by
instrument;
may be
expressed as
>0.001
500
6.5 to 8.5
20
10
Absent
Absent
0.01
1.3
0.015
0.01
1.3
0.015
17
2013 Rockingham Results (n=81)
Std
Ave
Max/Extreme
% Exceeding
Std
0.3
0.04
0.42
2.5
Manganese (mg/L)
0.05
0.005
0.27
2.5
Hardness (mg/L)
180
138.2
393
39.5
Sulfate (mg/L)
250
13.1
74
0
2.0/4.0
0.17
1.8
0
500
379
1057
17.3
5.2
3.7 (<6.5)
8.3
0 (>8.5)
Test
Iron (mg/L)
Fluoride (mg/L)
Total Dissolved Solids (mg/L)
6.5 to 8.5
7.3
Sodium (mg/L)
20
69.3
294.7
44.4
Nitrate-N (mg/L)
10
3.25
13.79
4.9
Total Coliform Bacteria
ABSENT
--
--
51.9(present)
E. Coli Bacteria
ABSENT
--
--
7.4(present)
pH
18
2013 Rockingham Results (n=81)
Test
Std
Copper (mg/L) – First Draw
Copper (mg/L) – Flushed
1.0/1.3
Arsenic (mg/L) – First Draw
Arsenic (mg/L) – Flushed
0.010
Lead (mg/L) – First Draw
Lead (mg/L) – Flushed
0.015
Ave
Max/Extreme
% Exceeding
Std
0.23
6.80
1.2
0.021
0.39
0
ND
ND
0
ND
ND
0
0.006
0.14
8.6
ND
0.006
0
19

Cannot be smelled, tasted or seen

Coliform bacteria is an indicator
organism – means disease-causing
bacteria may be present

Public standard is 0 colony forming
units (cfu)/100 mL (ABSENT)

If present, test for fecal coliform or
E. coli presence – indicator that
sewage or animal waste is present.
Photo credits: www.water-research.net, www.britannica.com
Coliform Bacteria
20
If Coliform Bacteria are PRESENT

Don’t panic!

Examine well for pathways surface water can
enter well (cracks in casing), make sure
sanitary well cap is installed and secure,
ground slopes away from well, etc.

Consider shock chlorination

Retest after shock chlorination

Long term treatment options: ozonation, UV
light, continuous chlorination
21
http://www.kimicontrol.com/microorg/escherichia_coli.jpg
If E. Coli Bacteria are PRESENT

Take immediate steps to address

Shock chlorinate

Retest water

In the meantime, consider boiling or use
another source of water for drinking or
cooking

Check for potential contamination sources

Consider long-term treatment options: UV
light, ozonation, continuous disinfection
22
pH



Measure of the
acidity or
alkalinity of a
substance (0 –
14) scale
Logarithmic scale:
pH = 5 is 100
times more acidic
than pH = 7
Good indicator of
general water
quality
Increasing acidity
0
1
2
Battery acid
Gastric acid
Lemon juice
3
Vinegar
4
Neutral
5
Coffee
6
Milk
Distilled water
7
8
9
Recommended
pH range
6.5 – 8.5
Baking soda
Sea water
10
Increasing alkalinity 11
12
13
14
Milk of magnesia
Ammonia
Bleach
Lye
23
Corrosive Water

Also called aggressive water

Corrodes metal plumbing – can leach metals, causes pitting
and leaks, reduces length of appliance life

Most commonly caused by low pH; other contributing factors
include alkalinity, temperature, TDS levels

EPA recommends drinking water be non-corrosive

Excess copper or lead in drinking water is a health concern

Depending on pH, treat with acid neutralizing filter or
soda ash injection
http://www.bushman.cc/photos/Copper_Water_Pipe_Corrosion.jpg; http://www.cee.vt.edu/ewr/environmental/teach/wtprimer/corrosion/corrosion.html
24
Corrosive Water: Metals of concern

Lead
◦ Many serious health effects, especially in children and infants
 Developmental, neurological, reproductive and renal
◦ EPA MCL is 0 mg/L with a health action level of 0.015 mg/L.
◦ Sources include:
 Pipes in older homes (pre-1930)
 Solder in homes built prior to 1986
 “Lead-free” brass fixtures (<8%) – even in NEW homes!

Copper
◦ High levels can cause nausea, vomiting, stomach cramps; infants and
children particularly sensitive
◦ EPA MCL is 1.3 mg/L
◦ Nuisance effects noticeable at 1.0 mg/L
http://www.gravitaexim.com/images/Lead-pipe.jpg
25
Addressing Lead or Copper in Water

Options to consider:
◦ Discuss test results with your physician if concerned!
◦ Metals will be highest with corrosive water and contact time
with pipes. Flushing pipes may address problem. Make sure
that water runs until it is as cold as it gets before drinking
◦ Activated carbon filter (e.g. Brita)
 MAKE SURE IT IS LABELED TO REMOVE LEAD
 MAKE SURE TO CHANGE AS DIRECTED
◦ Address corrosivity of water – if pH < 6.5, can use acid
neutralizing filter; however, corrosivity can be caused by other
factors as well
◦ Reverse Osmosis
◦ Use another source of water known to be safe
26
http://wi.water.usgs.gov/pubs/FS-221-95/p2.gif
Nitrate (NO3-N)

Serious health concern for infants
◦ Methemoglobinemia or “blue baby syndrome”
 Nitrate  nitrite during digestion and blood cannot carry oxygen
◦ MCL 10 mg/L NO3-N or 45 mg/L of NO3
 If 3-5 mg/L, use do not use water for infants under 6 months

Sources include fertilizer, animal manure, sewage

NO3 dissolves and moves easily through soil

Test in spring months; levels change over time

BOILING INCREASES concentration of nitrates!!!

Treatment: distillation, reverse osmosis, ion exchange
27
www.goodcleanwater.com/fyi.htm; www.watersoftening.org/effects_of_hard_water.htm;
Hardness/Scaling

Hard water contains high levels of
and magnesium ions
calcium
◦ Dissolved into water during contact with
limestone and other minerals

Not a health risk – nuisance
◦ Decreased cleaning action of soaps, detergents
◦ Scale build-up in pipes and on appliances
◦ Reduced efficiency and lifespan of water heaters

No EPA standard for public systems

Treat using water softener
Hardness Rating
Grains per Gallon
mg/L
Soft
Less than 1.0
Less than 17.1
Slightly-Moderately Hard
1.0-7.0
17.1-120
Hard
7.0-10.5
120-180
Very Hard
Over 10.5
Over 180
28
/www.cotrip.org/winterdriving/images/pic6.jpg; /www.apswater.com/images/fleck%205600.jpg
Sodium

Low levels occur naturally; high levels may
from man-made source
be
◦ Road salt storage or application
◦ Industrial waste
◦ Sewage, fertilizers or animal waste
◦ WATER SOFTENER

Sodium: EPA recommendation for people on low-sodium diets:
20 mg/L

Consider other sources of salt in diet and discuss with Dr.

Higher levels may indicate contamination – test for bacteria or
other contaminants

Salty taste; and may accelerate corrosion of pipes and water
heaters

Treat using distillation, reverse osmosis, demineralization
29
Total Dissolved Solids (TDS)

Water is a great solvent – dissolves many compounds
as it travels over and under ground

TDS is a measure of all dissolved impurities

Natural sources: limestone, salt deposits, other minerals

Man-made sources:
◦ Septic systems and sewage
◦ Run off from agricultural or urban land
◦ Road salt, industrial sources

General indicator of water quality;
test at least every three years

EPA SMCL is 500 mg/L

Treat using distillation or reverse osmosis
http://en.wikipedia.org/wiki/Total_dissolved_solids
30
http://www.freedrinkingwater.com/images-water-quality/chemicals/water%20in%20reddish-brown.jpg
Iron and Manganese

Nuisance - not health concern

SMCL: Iron = 0.3 mg/L; Mn = 0.05 mg/L

Red-brown/black staining, particles,
metallic taste

Treatment depends on type/form of iron
◦ Ferrous: water initially clear  orange-brown
black solid particles
◦ Ferric: solid particles apparent immediately,
water has a tint
or
or
◦ Iron bacteria: not a health concern; feed on Fe and Mn,
forming red-brown or black-brown slime

Treatment: water softener, aeration and filtration,
ozonation, distillation
31
Virginia Master Well Owner Network
Training Workshop
Want to learn more about
your private water supply?
Visit www.wellwater.bse.vt.edu
TRAINING WORKSHOPS TO BE HELD IN 2014
Contact Erin Ling
wellwater@vt.edu
540-231-9058
32
Cristin Sprenger (cristinc@vt.edu)
Amber Vallotton (avallott@vt.edu)
Virginia Household Water Quality Program
Virginia Master Well Owner Network
Erin Ling (wellwater@vt.edu)
Brian Benham (benham@vt.edu)
www.wellwater.bse.vt.edu
Email: wellwater@vt.edu
Ph: 540-231-9058
33
Resources

Virginia Household Water Quality Program www.wellwater.bse.vt.edu

Virginia Certified Lab Listing:
http://www.wellwater.bse.vt.edu/files/Labslist2013.pdf

EPA Private Wells Site
http://www.epa.gov/ogwdw/privatewells/whatyoucando.html

National Groundwater Association Well Owner
http://www.wellowner.org/

Water Systems Council Wellcare Hotline
http://www.wellcarehotline.org/

National Sanitation Foundation: www.nsf.org

Water Quality Association: www.wqa.org

Consumer Reports or Better Business Bureau
www.consumerreports.org OR www.bbb.org
34
End of slide show. Additional slides follow if
you wish to add them.
35
Arsenic

Occurs naturally in some rocks; more common in
groundwater supplies when water tables rise and fall
frequently

Used in wood preservatives, paints, pesticides, etc.

Linked to many types of cancer, stomach pain, paralysis,
and blindness

EPA primary standard is 0.010 mg/L

Reverse osmosis to remove
36
Fluoride

Occurs naturally in varying levels
◦ Naturally high levels of F in E. Virginia groundwater

Added to many public water systems for reduced
dental caries and strong teeth and bones

Health concerns:
◦ Long term exposure: links to bone cancer
◦ Shorter term exposure: dental or skeletal fluorosis

EPA MCL 4.0 mg/L and SMCL 2.0 mg/L

Optimum levels for public systems 0.8 - 1.2 mg/L

Limited use for children up to 8 years

Treatment (reverse osmosis) removes ALL fluoride
http://www.willamettedental.com/en_us/ALL/patients/pps/retailproducts_prettysmile.gif; http://en.wikipedia.org/wiki/Dental_fluorosis
37
Treatment Options
Primary Problem
Treatment Method
Notes
Corrosive water, copper,
lead, leaks
Acid neutralization
Uses limestone chips or soda
ash to increase water pH and
hardness to prevent corrosion
Arsenic, fluoride
Activated alumina
Water pH must be less than 8.5
Pretreatment with oxidation
may be necessary to achieve
good arsenic removal
Hydrogen sulfide,
Aeration
methane, volatile organics,
radon
Expensive and susceptible to
cogging by other pollutants but
very effective when multiple
gases are present
Sulfate, nitrate, arsenic
Anion exchange
Increases chloride
concentration in treated water.
May make water more
corrosive.
Chlorine, pesticides,
herbicides, radon,
miscellaneous tastes and
odors, volatile organics
Carbon filter
Disinfection should be used on
water supplies with bacterial
contamination because
bacteria can multiply in filter.
Carbon must be replaced
periodically.
Adapted from Tips for Buying Water Treatment Equipment by Stephanie Clemens and Bryan Swistock, Penn State University
38
Treatment Options
Primary Problem
Treatment Method Notes
Bacteria, iron and
manganese
Chlorination
Water must be clear for chlorine to
work. Requires tank for storage
and contact time.
Removes everything
except volatile organics,
pesticides, herbicides
Distillation
Produces small amounts of blandtasting water. Space needed to
store treated water.
Iron, manganese,
hydrogen sulfide
Oxidizing filters
Periodic addition of chemicals and
backwashing is necessary. Good
option when all three are present.
Bacteria, metals, odors,
tastes
Ozone
Expensive to purchase and operate
but very effective at removing
multiple pollutants.
All dissolved pollutants
Reverse osmosis
Produces small amounts of water
and some waste water. Will not
remove most organic pollutants or
bacteria
Adapted from Tips for Buying Water Treatment Equipment by Stephanie Clemens and Bryan Swistock, Penn State University
39
Treatment Options
Primary Problem
Treatment Method Notes
Soil, sand, other particles
Sediment filter
Must be routinely changed or
backwashed
Removes scale or
hardness and limited
amounts of dissolved iron
and manganese
Softener
Causes increase in water sodium
level. Water may become more
corrosive after softening.
Bacteria
Ultraviolet light
Water must be free of sediment to
kill bacteria effectively. Change
bulb annually.
Adapted from Tips for Buying Water Treatment Equipment by Stephanie Clemens and Bryan Swistock, Penn State University
40
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