400 likes | 412 Views
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.
E N D
Rockingham CountyDrinking Water ClinicInterpretation MeetingCristin Sprenger and Amber VallottonVirginia Cooperative ExtensionErin Ling and Brian BenhamVirginia 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!
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
Proper well location and construction • 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” Photo credits: SAIF Water Wells ; Penn State University 12”
The Finished Product – Drilled Well Sealed, sanitary well cap Casing extending >12” above ground surface Ground sloping away from casing Grout seal 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)
Private Water Supply Regulations • Virginia Private Well Regulations • Specify application, inspection and construction requirements • No requirements for maintenance or water testing after construction of well – responsibility of the owner! • EPA National Drinking Water Standards • Apply to PUBLIC systems • Primary (health) and Secondary (nuisance) • Can be used as guidance for private systems to know “how much is too much”
EPA Drinking Water Standards Primary Standards • Also called Maximum Contaminant Level (MCL) • Cause health problems • Enforced for public systems • Over 80 contaminants • For example: • Nitrate • Lead • Coliform • Most organic chemicals and pesticides Secondary Standards • Also called SMCL or RMCL • Cause aesthetic problems: • Staining • Taste • Odor • Can naturally occur in ground water • About 15, including: • Iron • Sulfate • Manganese
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
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
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!
Household water quality is complex! Well location Well construction Well maintenance Hydrogeology Local land uses Surface activities Water Treatment Plumbing Photo credits: Penn State Univ., http://www.banthebagspdx.com/?p=283, USGS; http://www.clker.com/clipart-puzzle-pieces-2.html; 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 Source may be plumbing materials or existing water treatment device: sodium copper lead 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: arsenic TDS sodium iron chloride hardness pH/corrosivity fluoride sulfate nitrate manganese
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 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
SAMPLE Test Report ** = exceeds recommended level ND = not detected by instrument; may be expressed as >0.001
Coliform Bacteria • 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
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
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 http://www.kimicontrol.com/microorg/escherichia_coli.jpg
pH 0 Battery acid 1 Gastric acid • 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 2 Lemon juice Increasing acidity 3 Vinegar 4 5 Coffee Recommended pH range 6.5 – 8.5 6 Milk Neutral Distilled water 7 8 Baking soda 9 Sea water 10 Milk of magnesia Increasing alkalinity 11 12 Ammonia 13 Bleach Lye 14
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
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
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
Nitrate (NO3-N) http://wi.water.usgs.gov/pubs/FS-221-95/p2.gif • 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
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 www.goodcleanwater.com/fyi.htm; www.watersoftening.org/effects_of_hard_water.htm; 28
Sodium • Low levels occur naturally; high levels may be from man-made source • 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 /www.cotrip.org/winterdriving/images/pic6.jpg; /www.apswater.com/images/fleck%205600.jpg
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 30 http://en.wikipedia.org/wiki/Total_dissolved_solids
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 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 http://www.freedrinkingwater.com/images-water-quality/chemicals/water%20in%20reddish-brown.jpg
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 Learn more about your water! Help Others! Apply today! Free Resource Binder!
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
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
End of slide show. Additional slides follow if you wish to add them.
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
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
Treatment Options Adapted from Tips for Buying Water Treatment Equipment by Stephanie Clemens and Bryan Swistock, Penn State University
Treatment Options Adapted from Tips for Buying Water Treatment Equipment by Stephanie Clemens and Bryan Swistock, Penn State University
Treatment Options Adapted from Tips for Buying Water Treatment Equipment by Stephanie Clemens and Bryan Swistock, Penn State University