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County Drinking Water Clinic Interpretation Meeting Erin James Ling and Brian Benham Biological Systems Engineering Department Virginia Tech Why are we here? • How to care for your private water system • Well location, protection, and construction • Well maintenance and care • Drinking water regulations – knowing how much is too much • Water testing – what’s in your water? • Dealing with problems • Additional resources 2 Private Water Supplies in Virginia Majority of households in 60 of Virginia’s 95 counties rely on private water supply systems (> 1,500,000 homes) In 52 counties, the number of households using private wells is increasing faster than the number connecting to public systems (VADEQ, 2007) 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 3 How does water move to my well? In this part of Virginia, groundwater moves through fractures, or cracks in the bedrock Water can come from many different directions and sources into one well It can take water hours, days, or years to move through 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 4 Photo credit: Swistock, Penn State Univ Proper well location Well should be at least: ◦ 5 feet from property boundary ◦ 10 feet from building foundation (50 feet if termite treated) ◦ 50 feet from road ◦ 50 feet from sewers and septic tanks ◦ 100 feet from pastures, on-lot sewage system drainfields, cesspools or barnyards Upslope from potential contamination Not in an area that receives runoff 5 Proper well construction Contract a licensed driller: ◦ Valid Class A, B or C contractor license with WWP (Water Well and Pump) classification Well casing ◦ Minimum of 20’ for bored, 50 – 100’ deep for drilled, depending on class of well ◦ Extends 12” above ground Grouting to a minimum of 20’ Sanitary well cap or sealed concrete cover Ground slopes away from well 12” Photo credits: SAIF Water Wells ; Penn State University 6 The Finished Product – Drilled Well 7 http://www.omafra.gov.on.ca/english/environment/06-117.htm Well Maintenance Tips Do not use fertilizers, pesticides, oil, or paint around 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 10 years have well inspected by a qualified professional (with WWP classification) 8 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” 9 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 Fluoride o Chloride 10 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 11 What should I test for? Every year test for coliform bacteria ◦ Simple, inexpensive test ($15-20) ◦ 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 12 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 ◦ Radon, hardness, pH Compare to EPA standards: http://www.epa.gov/safewater/contaminants/index.html 13 Sources of potential contaminants or issues of concern well Surface water contamination: nitrate, bacteria Source may be plumbing materials or existing water treatment device: sodium copper lead bacteria Often found in groundwater naturally, may be due to human activities on or below ground: TDS iron hardness 14 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 public water 15 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 Be aware of unscrupulous businesses – 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) Weigh benefits and limitations of a device: ◦ Cost ◦ Maintenance requirements ◦ Warranty 16 SAMPLE Test Report Test Iron (mg/L) Household Water Recommended Maximum Sample or Range 0.02 0.3 <0.001 0.05 Hardness (mg/L) 44.5 180 Sulfate (mg/L) 2.066 250 Chloride (mg/L) 30 250 Fluoride (mg/L) < 0.1 2.0 Total Dissolved Solids (mg/L) 102 500 pH 6.2** 6.5 to 8.5 Copper (mg/L) 0.04 1.0 Sodium (mg/L) 7.8 20 Nitrate-N (mg/L) 4 10 PRESENT** ABSENT ABSENT ABSENT Manganese (mg/L) Total Coliform Bacteria E. Coli Bacteria ** measured value exceeds recommendation for household water 17 Cannot be smelled, tasted or seen Coliform bacteria is an indicator organism – means diseasecausing 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 18 If Coliform Bacteria are PRESENT Don’t panic! May consider retesting to ensure crosscontamination wasn’t the problem ◦ List available at http://www.wellwater.bse.vt.edu/resources.php Examine well or spring for damage Consider shock chlorination Long term treatment: ozonation, UV light, continuous chlorination 19 http://www.kimicontrol.com/microorg/escherichia_coli.jpg If E. Coli Bacteria are PRESENT Take immediate steps to address Shock chlorinate Check for potential contamination sources Retest water after shocking In the meantime, consider boiling or use another source of water for drinking or cooking Consider long-term treatment options: UV light, ozonation, continuous disinfection 20 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 21 Corrosive Water: Metals of concern Lead ◦ Many serious health effects, especially in children and infants Developmental, neurological, reproductive and renal ◦ EPA MCL is 0 µg/L with a 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 22 www.goodcleanwater.com/fyi.htm; www.watersoftening.org/effects_of_hard_water.htm; Hardness/Scaling Hard water contains high levels of calcium and magnesium ions ◦ 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 23 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 Treat using distillation or reverse osmosis http://en.wikipedia.org/wiki/Total_dissolved_solids 24 /www.cotrip.org/winterdriving/images/pic6.jpg; /www.apswater.com/images/fleck%205600.jpg Sodium and Chloride Low levels occur naturally; high levels from man-made source usually ◦ Road salt storage or application ◦ Industrial waste ◦ Sewage, fertilizers or animal waste ◦ WATER SOFTENER 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 contaminants Salty taste; and may accelerate corrosion of pipes and water heaters Treat using distillation, reverse osmosis, demineralization 25 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 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 ◦ CL 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 thepipelinefixation.blogspot.com Hydrogen Sulfide Colorless gas; rotten egg smell Not regulated by EPA – people can detect low levels Naturally present in shale, sandstone, near coal or oil fields Sulfur-reducing bacteria produce (not a health risk) Treatment depends on concentration, so 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 28 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 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 Treatment: water softener, aeration and filtration, ozonation, distillation 29 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 30 Virginia Master Well Owner Network Training Workshop New opportunity for private water supply users! Visit www.wellwater.bse.vt.edu today to find out more and complete an application or contact Erin James Ling [email protected] 540-231-9058 31 Contact Us Barry Robinson Montgomery Co Extension [email protected] (540) 382-5790 Erin James Ling Virginia Household Water Quality Program and Master Well Owner Network Coordinator [email protected] 540-231-9058 Brian Benham Virginia Tech Biological Systems Engineering Extension Specialist [email protected] 540-231-5705 Visit our Private Water Supply Protection Website: www.wellwater.bse.vt.edu 32 Resources Virginia Household Water Quality Program www.wellwater.bse.vt.edu Virginia Certified Lab Listing http://www.dgs.state.va.us/divisionofconsolidatedlaboratoryservices/ services/laboratorycertification/tabid/508/default.aspx 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 33 Questions? 34 Local land uses Mining Iron Manganese pH Residential Development Bacteria Nitrates Sediment Lawn Chemicals Agriculture Nitrates Bacteria Pesticides Roads Sodium Chloride Industry or Landfill Petroleum VOC’s 35 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 36 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, methane, volatile organics, radon Aeration 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, Carbon filter herbicides, radon, miscellaneous tastes and odors, volatile organics 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 37 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 bland-tasting 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 38 Treatment Options Primary Problem Treatment Method Notes Soil, sand, other particles Sediment filter Must be routinely changed or backwashed Removes scale or Softener hardness and limited amounts of dissolved iron and manganese Causes increase in water sodium level. Water may become more corrosive after softening. Bacteria Water must be free of sediment to kill bacteria effectively. Change bulb annually. Ultraviolet light Adapted from Tips for Buying Water Treatment Equipment by Stephanie Clemens and Bryan Swistock, Penn State University 39