Transcript Water Resources Extension at Penn State University

Water Quality Contaminants
of Concern
Erin James
Virginia Tech Biological Systems Engineering
Virginia Master Well Owner Network Training
October 29-30, 2008
Harrisonburg Virginia
Overview
 General recommendations of VAHWQP and
VAMWON
 EPA public drinking water standards
 General water quality indicators
 Specific health concerns, nuisance problems, or
nearby landuses
 Specific contaminants common in VA
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General VAHWQP Recommendations
 Test every year for bacteria
 Test every three years for pH, TDS, any local
pollutants
 Test before new nearby activity - legal protection!
 Test if there are infants or people with
compromised immune systems in your home
 Test if change in odor, appearance or taste
 Always recommend testing through a certified lab
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EPA Drinking Water Standards
Primary Standards
Secondary Standards
• Also called Maximum
Contaminant Level (MCL)
• Cause health problems
• Enforced for public systems
• Over 80 contaminants
• For example:
 Also called SMCL or RMCL
Nitrate
o Lead
o Coliform
o Most organic chemicals and
pesticides
o
 Cause aesthetic problems:
Staining
o Taste
o Odor
o
 Can naturally occur in ground
water
 About 15 contaminants including:
Iron
o Fluoride
o Chloride
o
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General Water Quality Indicators
Indicator
Acceptable Limit
Indication
Coliform bacteria
< I coliform/100 ml
Possible bacterial or viral contamination
from human or animal waste
pH
6.5 to 8.5
Important overall measure of water
quality; pH can alter corrosivitiy and
solubility of contaminants.
Low pH: pitting of pipes and fixtures,
metallic taste
High pH: water has slippery feel, soda
taste
Total dissolved
solids
500 mg/L
Dissolved metals, like iron or
manganese; hardness; salty, bitter taste
or staining.
Adapted from Interpreting your Water Test Report. 2001. Blake Ross and Kathleen Parrott (VCE pub 356-489)
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Tests for Specific Health Concerns
Situation
Recommended Tests
Family members or guests with recurring Coliform bacteria, nitrate, sulfate
incidents of gastrointestinal illness
Household plumbing contains lead
pipes, fittings or solder joints or brass
pH, corrosion index, lead, copper,
cadmium, zinc
Household with pregnant woman or
young infant
Coliform bacteria, nitrate
Family member on recommended lowsodium diet
Sodium
Adapted from Household Water Testing. 2000. Blake Ross, Kathleen Parrott, and Janice Woodward (VCE pub 356-485)
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Coliform Bacteria
 Cannot be smelled, tasted or seen
 Coliform bacteria is an indicator
organism – means diseasecausing bacteria may be present
 Public standard is 0 cfu/100mL
 If present, test for fecal coliform or
E. coli presence – strong indicator
that sewage or animal waste is
present.
Photo credits: www.water-research.net, www.britannica.com
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Nuisance Problems
Symptom
Description
Recommended Tests
Stained plumbing
fixtures
Red or brown
Reddish-brown slime
Black
Green or Blue
Chalky white
Iron
Iron bacteria
Manganese
Copper
Hardness
Off-color water
Cloudy
Black
Brown or yellow
Turbidity, suspended solids
Hydrogen sulfide, Mn
Iron, tannic acid
Unusual taste or odor
Rotten egg
Metallic
Salty
Septic, musty, earthy
Alkali, bitter
Gasoline or oil
Soapy
Hydrogen sulfide
pH, corrosivity, Fe, Cu, Zn, Pb
TDS, chloride, sodium
Coliform, methane
pH, TDS
Hydrocarbon scan
Surfactants or detergents
Corrosive water
Deposits, pitting of
plumbing
Corrosivity, pH, copper, lead
Adapted from Household Water Testing. 2000. Blake Ross, Kathleen Parrott, and Janice Woodward (VCE pub 356-485)
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Nuisance problems
http://www.process-controls.com/techsales/Dynamic_Descaler/images/before_1.jpg, www.tamhil.com/english/content.asp?id=24
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Nuisance problems
Photo credits: www.ehrenner.com/Chloronation.html, www.bookofjoe.com/2006/01/13/index.html, cleanwellwater.com/acidic_water_bluegreen_stains
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Nuisance problems
Photo credits: Midland Corrosion Associates, www.awqinc.com/ph.html, www.ehrenner.com/Chloronation.html,
http://www.copper.org/applications/plumbing/techcorner/images/erosion_corrosion.jpg
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Tests for Specific Contamination
If you suspect or observe
Recommended Tests
Leaking fuel tank
Hydrocarbon scan
Coal mining
TDS, iron, sulfate, pH, corrosivity,
manganese, aluminum
Gas or oil drilling
TDS, chloride, sodium, barium, lead,
pH, corrosivity, strontium
Road salt storage or application
TDS, chloride, sodium
Landfill or dump
TDS, pH, chemical oxygen demand,
VOC scan, heavy metals
Land application of sludge
Total coliform, nitrate, heavy metals
Septic system
Fecal coliform/E. coli, fecal
streptococcus, nitrate, surfactants
Intensive agricultural use
Total coliform, nitrate, pesticide scan,
pH, TDS
Adapted from Household Water Testing. 2000. Blake Ross, Kathleen Parrott, and Janice Woodward (VCE pub 356-485)
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Conditions or nearby activities of concern
Conditions or Nearby Activities
Test for:
Recurring gastro-intestinal illness
Coliform bacteria
Household plumbing contains lead
pH, lead, copper
Radon in indoor air
Radon
Corrosion of pipes and plumbing
Corrosivity, pH, lead
Nearby areas of intensive agriculture
Nitrate, pesticides, coliform bacteria
Coal or other mining operations
Metals, pH, corrosivity
Dump, junkyard or landfill
VOCs, TDS, pH, sulfate, chloride, metals
Odor of gasoline or fuel oil
VOCs
Objectionable taste or smell of water
Hydrogen sulfide, corrosivity, metals
Stained plumbing fixtures or laundry
Iron, copper, manganese
Salty taste
Chloride, TDS, sodium
Scaly residues, soaps don’t lather
Hardness
Rapid wear of water equipment
pH, corrosivity
Water is cloudy, frothy or colored
Colors, detergents
Adapted from “Drinking Water for Household Wells”, EPA, 2002
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Most common contaminants in Virginia
 Iron and manganese
 Bacteria
 Hardness
 Corrosive and Scaling Water
 Hydrogen Sulfide
 Nitrate
 Sodium
 TDS
 Fluoride
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Iron and Manganese
 Nuisance - not health concern
 SMCL:
Iron = 0.3 mg/L
Manganese = 0.05 mg/L
 Red-brown/black staining, particles, metallic taste
 Treatment depends on type/form of iron
 Ferrous: water initially clear  orange-brown or black
solid particles
 Ferric: solid particles apparent immediately, or water has
a tint
 Iron bacteria – not a health concern; feed on Fe and Mn,
forming red-brown or black-brown slime
http://www.freedrinkingwater.com/images-water-quality/chemicals/water%20in%20reddish-brown.jpg
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http://bcn.boulder.co.us/basin/data/BACT/info/FColi.html
Bacteria
 Coliform an indicator of potential for other
pathogens:
 Dysentery, Hepatitis, Typhoid, Cholera, Giardia,
Cryptosporidia
 Sources:
 Human and animal waste (septic tank, barnyard runoff)
 Insects, small animals in poorly sealed wells
 Flooding; older or shallow wells without air-tight seal
 Laboratory test:
 EPA MCL for public supplies is 0 cfu/100mL
 Reported as presence/absence, cfu (colony forming
units)/100 mL, or MPN (most probable number)
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www.goodcleanwater.com/fyi.htm
Hardness
 Hard water contains high levels of calcium
and magnesium ions
 Dissolved into water during contact with limestone, 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
Hardness Rating
Soft
Grains per Gallon
Mg/L
Less than 1.0
Less than 17.1
Slightly Hard
1.0-3.5
17.1-60
Moderately Hard
3.5-7.0
60-120
Hard
7.0-10.5
120-180
Over 10.5
Over 180
Very Hard
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Corrosive and Scaling Water
 Measure of alkalinity, TDS, and pH
 Corrosive (aggressive) water
 Corrodes metal in plumbing, causing damage, pitting
 Leaching of copper or lead into drinking water – health
concern!
 EPA recommends drinking water be non-corrosive
 Scaling water
 Contains high levels of minerals
 Forms scale on inside of pipes and appliances, lime
deposits on shower heads and taps
 Can lead to clogging of pipes, reduced efficiency of heaters
and appliances
http://www.bushman.cc/photos/Copper_Water_Pipe_Corrosion.jpg; www.watersoftening.org/effects_of_hard_water.htm
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Corrosive and Scaling Water
 Usually a measure of alkalinity, TDS, and pH; often
reported as a Saturation Index (varies by lab)
Langelier Saturation
Index (LSI)
Description
Recommendation
-5 to -3
Severe corrosion
Treatment recommended
-3 to -1
Moderate corrosion
Consider treatment
1- to 1
Balanced
Treatment not needed
1 to 3
Moderate scaling
Consider treatment
3 to 5
Severe scaling
Treatment recommended
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Corrosive Water: Metals of concern
 Lead
 Many serious health effects, esp in children and infants

Developmental, neurological, reproductive and renal
 EPA MCL is 0 µg/L with an HAL (health action level) of 15 µg/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
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thepipelinefixation.blogspot.com
Hydrogen Sulfide
 Colorless gas; rotten egg smell
 Not regulated by EPA – most people can detect at very
low levels
 Naturally present in shale, sandstone, near coal or oil
fields
 Produced by sulfur-reducing bacteria (not a health risk)
 Treatment depends on concentration, so you must test
 Only noticeable in hot water?
 Bacteria could be thriving in your water heater
 Sulfates may be converted to H2S chemically in your water heater during a
reaction with your magnesium corrosion control rod
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Nitrate (NO3)
 Serious health concern for infants
 Methemoglobinemia or “blue baby syndrome”



Nitrate becomes nitrite in digestive system, which forms
methemoglobin rather than hemoglobin (does not carry oxygen)
EPA MCL 10 mg/L NO3-N (nitrate nitrogen) or 45 mg/L of NO3 (nitrate)
If levels approach 3-5 mg/L, use another source of 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
 NOTE that BOILING INCREASES concentration of
nitrates!!!
http://wi.water.usgs.gov/pubs/FS-221-95/p2.gif
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Sodium and Chloride
 Low levels occur naturally
 Higher levels usually from man-made source
 Road salt storage or application
 Industrial waste
 Sewage, fertilizers or animal waste
 In coastal areas, salt water intrusion
 Sodium: EPA MCL for people on low-sodium diets: 20 mg/L
 Chloride: EPA SMCL of 250 mg/L
 Higher levels may indicate contamination – test for bacteria
or other chemicals
 Salty taste; and may accelerate corrosion of pipes and
water heaters
http://www.cotrip.org/winterdriving/images/pic6.jpg
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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 < 2µm dia
 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
http://en.wikipedia.org/wiki/Total_dissolved_solids
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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
http://www.willamettedental.com/en_us/ALL/patients/pps/retailproducts_prettysmile.gif; http://en.wikipedia.org/wiki/Dental_fluorosis
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What do you recall about…..
 Iron and manganese
 Bacteria
 Hardness
 Corrosive and Scaling Water
 Hydrogen Sulfide
 Nitrate
 Sodium
 TDS
 Fluoride
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