erin james virginia master well owner network training water quality contaminants of concern

Download Erin James Virginia Master Well Owner Network Training Water Quality Contaminants of Concern

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Erin James Virginia Master Well Owner Network Training Water Quality Contaminants of Concern Slide 2 2 Sources of potential contaminants or issues of concern pH/corrosivity hardness nitrate fluoride TDS iron manganese sulfate chloride sodium 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 mans activities on or below ground: well Slide 3 Testing water quality Why test? Protect familys 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 3 Slide 4 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 4 Slide 5 Understanding test results Most results provided as concentrations: mg/L (milligrams per liter) ppm (parts per million) g/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 5 Slide 6 Private Water Supply Regulations 6 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 Slide 7 EPA Drinking Water Standards Primary Standards Also called Maximum Contaminant Level (MCL) Cause health problems Enforced for public systems Over 80 contaminants For example: o Nitrate o Lead o Coliform o Most organic chemicals and pesticides Secondary Standards Also called SMCL or RMCL Cause aesthetic problems: o Staining o Taste o Odor Can naturally occur in ground water About 15 contaminants including: o Iron o Fluoride o Chloride 7 Slide 8 Tests for Specific Health Concerns 8 SituationRecommended Tests Family members or guests with recurring incidents of gastrointestinal illness Coliform bacteria, nitrate, sulfate 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 low-sodium diet Sodium Adapted from Household Water Testing. 2000. Blake Ross, Kathleen Parrott, and Janice Woodward (VCE pub 356-485) Slide 9 Tests based on nearby land use 9 If you suspect or observeRecommended Tests Leaking fuel tankHydrocarbon scan Coal miningTDS, iron, sulfate, pH, corrosivity, manganese, aluminum Gas or oil drillingTDS, chloride, sodium, barium, lead, pH, corrosivity, strontium Road salt storage or applicationTDS, chloride, sodium Landfill or dumpTDS, pH, chemical oxygen demand, VOC scan, heavy metals Land application of sludgeTotal coliform, nitrate, heavy metals Septic systemFecal coliform/E. coli, nitrate, surfactants Intensive agricultural useTotal coliform, nitrate, pesticide scan, pH, TDS Adapted from Household Water Testing. 2000. Blake Ross, Kathleen Parrott, and Janice Woodward (VCE pub 356-485) Slide 10 Nuisance Problems 10 SymptomDescriptionRecommended Tests Stained plumbing fixtures Red or brown Reddish-brown slime Black Green or Blue Chalky white Iron Iron bacteria Manganese Copper Hardness Off-color waterCloudy Black Brown or yellow Turbidity, suspended solids Hydrogen sulfide, Mn Iron, tannic acid Unusual taste or odorRotten 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 waterDeposits, pitting of plumbing Corrosivity, pH, copper, lead Adapted from Household Water Testing. 2000. Blake Ross, Kathleen Parrott, and Janice Woodward (VCE pub 356-485) Slide 11 Coliform Bacteria Cannot be smelled, tasted or seen Coliform bacteria is an indicator organism means disease-causing pathogens may be present (e.g., Dysentery, Hepatitis, Typhoid, Cholera, Giardia) Public standard is 0 colony forming units(cfu)/100 mL (ABSENT) Sources: Human and animal waste Insects, small animals in poorly sealed wells Flooding; older or shallow wells without sanitary well cap 11 Photo credits: www.water-research.net, www.britannica.com Slide 12 If Coliform Bacteria are PRESENT Dont panic! Recommend RETEST Use certified lab Follow with test for E. Coli bacteria Take this as an opportunity to examine well or spring for damage or needed improvements Consider shock chlorination Long term treatment options: ozonation, UV light, continuous chlorination 12 Slide 13 If E. Coli Bacteria are PRESENT Take immediate steps to address Shock chlorinate Retest water In the meantime, consider boiling for at least 3 minutes or use another source of water for drinking or cooking Check for potential contamination sources, examine well or spring Consider long-term treatment options: UV light, ozonation, continuous disinfection 13 http://www.kimicontrol.com/microorg/escherichia_coli.jpg Slide 14 Nitrate (NO 3 -N) Serious health concern for infants < 6 mo Methemoglobinemia or blue baby syndrome Nitrate nitrite during digestion and blood cannot carry oxygen Sources include fertilizer, animal manure, sewage NO 3 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 14 http://wi.water.usgs.gov/pubs/FS-221-95/p2.gif Slide 15 pH Measure of whether a substance is acidic or alkaline Scale: 0 (acidic) to 14 (alkaline) pH of 5 is 100 times more acidic than pH of 7 (logarithmic scale) Good indicator of general water quality 1 2 3 4 5 6 7 0 8 9 10 12 11 14 13 more acidic more alkaline Neutral Lemon juice Vinegar Recommended pH range 6.5 8.5 Milk Battery acid Ammonia Milk of magnesia Baking soda Sea water Lye Distilled water Coffee Bleach Gastric acid Slide 16 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 16 http://www.bushman.cc/photos/Copper_Water_Pipe_Corrosion.jpg; www.watersoftening.org/effects_of_hard_water.htm Slide 17 Corrosive and Scaling Water Usually a measure of alkalinity, TDS, and pH; often reported as a Saturation Index (varies by lab) 17 Langelier Saturation Index (LSI) DescriptionRecommendation -5 to -3Severe corrosionTreatment recommended -3 to -1Moderate corrosionConsider treatment 1- to 1BalancedTreatment not needed 1 to 3Moderate scalingConsider treatment 3 to 5Severe scalingTreatment recommended Slide 18 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 18 http://www.bushman.cc/photos/Copper_Water_Pipe_Corrosion.jpg; http://www.cee.vt.edu/ewr/environmental/teach/wtprimer/corrosion/corrosion.html Slide 19 Corrosive Water: Metals of concern Lead Many serious health effects, especially in children and infants Developmental, neurological, reproductive and renal EPA MCL is 0 g/L with a health action level of 15 g/L. Sources include: Pipes in older homes (pre-1930) Solder in homes built prior to 1986 Lead-free brass fixtures (

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